Zollinger-Ellison syndrome – Group of symptoms that occur when a tumor called a gastrinoma forms in the pancreas. The tumor releases large amounts of the
hormone gastrin, which causes too much acid in the duodenum, resulting in ulcers, bleeding, and perforation.

zygote intrafallopian transfer (ZIFT) – method of treating infertility by removing eggs from a woman’s ovaries, fertilizing them in the laboratory with
sperm from her partner or a donor, and inserting one or more of the fertilized eggs into one of her fallopian tubes.

yellow fever – a viral disease that is transmitted by the Aedes aegypti mosquito.

Yin and Yang – Chinese words for complementary and opposite forces that make up the life force (Qi).

yoga – Indian word for "union." Yoga is a posturing and breathing technique to induce relaxation.

x-ray – a diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.

wart – a non-cancerous skin growth caused by a virus.

watermelon stomach – parallel red sores in the stomach that look like the stripes on a watermelon.

wedge resection of the lung – a small, localized section of the lung is removed – often for a lung biopsy.

white blood cells (Also called WBCs or leukocytes.) – blood cells involved in the destruction of viruses, bacteria, and fungi.

white matter – nerve tissue that is paler in color than gray matter because it contains nerve fibers with large amounts of insulating material (myelin).
The white matter does not contain nerve cells. In the brain, the white matter lies within the gray layer of the cerebral cortex.

whole blood – blood containing all its components, such as red and white blood cells, platelets, and more.

Wolff-Parkinson-White syndrome – An extra electrical pathway that connects the atria and ventricles and causes rapid heartbeat.

vacuum extraction – procedure used to ease delivery by applying a metal or plastic cup to the baby’s scalp and using suction to pull the baby gradually
out of the vagina.

vagina (Also called the birth canal.) – the passageway through which fluid passes out of the body during menstrual periods. The vagina connects the
cervix (the opening of the womb, or uterus) and the vulva (the external genitalia).

vaginal atrophy – often a symptom of menopause; the drying and thinning of the tissues of the vagina and urethra. This can lead to dyspareunia (pain
during sexual intercourse) as well as vaginitis, cystitis, and urinary tract infections.

vaginal hysterectomy – the uterus is removed through the vaginal opening.

vaginitis – inflammation, redness, or swelling of the vaginal tissues; usually resulting from a bacterial infection.

vaginitis, atrophic – a form of noninfectious vaginitis which usually results from a decrease in hormones because of menopause, surgical removal of the
ovaries, radiation therapy, or even after childbirth – particularly in breastfeeding women. Lack of estrogen dries and thins the vaginal tissue, and may also cause spotting.

vaginitis, bacterial – very common vaginal infection characterized by symptoms such as increased vaginal discharge or itching, burning, or redness in the
genital area.

vaginitis, noninfectious – a type of vaginitis that usually refers to vaginal irritation without an infection being present. Most often, the infection is
caused by an allergic reaction to, or irritation from, vaginal sprays, douches, or spermicidal products. It may also be caused by sensitivity to perfumed soaps, detergents, or fabric softeners.

vaginitis, viral – very common vaginal infection, often sexually transmitted, that is caused by one of many different types of viruses (i.e., herpes
simplex virus, human papillomavirus).

vagotomy – operation to cut the vagus nerve, which causes the stomach to produce less acid.

vagus nerve – nerve in the stomach that controls the production of stomach acid.

valgus deformity – a lateral inclination of a distal bone of a joint from the midline.

valve – fold in the lining of an organ that prevents fluid from flowing backward.

valves – the "doors" between the chambers of the heart. The heart valves are tricuspid, pulmonic, mitral, and aortic.

valvuloplasty – the repair of a heart valve using a balloon catheter inside the valve.

varices – stretched veins such as those that form in the esophagus from cirrhosis.

varicose veins – enlarged, curving veins just beneath the skin, usually in the legs.

varus deformity – a medial inclination of a distal bone of a joint from the midline.

vas deferens – the tubes leading to the testes.

vascular – pertaining to blood vessels.

vasculitis – inflamed blood vessels.

vasectomy – a surgical procedure performed to make a man sterile, or unable to father a child. It is a permanent male birth control measure, and a means
of contraception used in many parts of the world.

vasodepressors – a medication that raises blood pressure.

vasodilator – a medication that dilates or widens the opening in a blood vessel.

vein – a blood vessel that carries blood from the body back into the heart.

velocardiofacial syndrome – inherited disorder characterized by cleft palate, heart defects, characteristic facial appearance, minor learning problems,
and speech and feeding problems.

venipuncture – drawing blood with a needle from a vein usually in the forearm.

ventilation – movement of air (gases) in and out of the lungs.

ventricle – one of the two pumping chambers of the heart; right ventricle receives oxygen-poor blood from the right atrium and pumps it to the lungs
through the pulmonary artery; left ventricle receives oxygen-rich blood from the left atrium and pumps it to the body through the aorta.

ventricular fibrillation – a condition in which the ventricles contract in rapid and unsynchronized rhythms and cannot pump blood into the body.

ventricular tachycardia – a condition in which the ventricles cause a very fast heartbeat.

vernix caseosa (Also called vernix.) – a white substance that covers the skin of the fetus (while inside the uterus) and helps to protect the fetus.

vertebrae (Also called the back bone.) – bony structures that surround the spinal cord.

vertigo – illusion of movement; sensation that the external world is revolving around an individual (objective vertigo) or that the individual is
revolving in space (subjective vertigo).

vesicoureteral reflux (VUR) – the abnormal flow of urine from the bladder back into the ureters; often as a result of a urinary tract infection or birth
defect.

vestibular neuronitis – infection at the vestibular nerve.

vestibular system – system in the body that is responsible for maintaining the body’s orientation in space, balance, and posture; also regulates
locomotion and other movements and keeps objects in visual focus as the body moves.

vestibule – bony cavity of the inner ear.

vibrotactile aids – mechanical instruments that help individuals who are deaf detect and interpret sound through the sense of touch.

villi – tiny, fingerlike projections on the surface of the small intestine that help absorb nutrients.

viral hemorrhagic fevers – a term that refers to a group of illnesses caused by several distinct families of viruses. While some of these cause illnesses
that are relatively mild, many cause severe, life-threatening diseases with no known cure, such as the Ebola virus.

visual acuity – the space visible to an eye in a given position of gaze.

vitiligo – smooth, white patches in the skin caused by the loss of pigment-producing cells.

vitrectomy – an operation to remove the blood that sometimes collects at the back of the eyes when a person has eye disease.

vitreous body – a clear, jelly-like substance that fills the center of the eye.

vocal cord paralysis – inability of one or both vocal folds (vocal cords) to move because of damage to the brain or nerves.

vocal cords (Also called vocal folds.) – muscularized folds of mucous membrane that extend from the larynx (voice box) wall; enclosed in elastic vocal
ligament and muscle that control the tension and rate of vibration of the cords as air passes through them.

vocal tremor – trembling or shaking of one or more of the muscles of the larynx resulting in an unsteady-sounding voice.

voice – sound produced by air passing out through the larynx and upper respiratory tract.

voice disorders – group of problems involving abnormal pitch, loudness, or quality of the sound produced by the larynx (voice box).

volvulus – twisting of the stomach or large intestine.

vomiting – the release of stomach contents through the mouth.

vulva – external, visible part of the female genital area.

vulvitis – an inflammation of the vulva, the soft folds of skin outside the vagina. This is not a condition but rather a symptom that results from a host
of diseases, infections, injuries, allergies, and other irritants.

ulcerative colitis – a serious disease that causes ulcers and irritation in the inner lining of the colon and rectum.

ulnar bone – the longer of the two bones in the forearm.

ultrasound (Also called sonography.) – a diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood
vessels, tissues, and organs. Ultrasounds are used to view internal organs as they function, and to assess blood flow through various vessels.

ultraviolet radiation – invisible rays that come from the sun. Ultraviolet radiation can damage the skin and cause melanoma and other types of skin
cancer.

umbilical cord – a rope-like cord connecting the fetus to the placenta. The umbilical cord contains two arteries and a vein, which carry oxygen and
nutrients to the fetus and waste products away from the fetus.

umbilical cord blood transplant – a procedure in which stem cells are taken from an umbilical cord immediately after delivery of an infant.

umbilical hernia – a weakness in the abdominal muscles.

unilateral – affecting one side of the body. For example, unilateral kidney cancer occurs in one kidney only.

upper GI (gastrointestinal) series (Also called barium swallow.) – a diagnostic test that examines the organs of the upper part of the digestive system:
the esophagus, stomach, and duodenum (the first section of the small intestine). A fluid called barium (a metallic, chemical, chalky, liquid used to coat the inside of organs so that they will show up on an x-ray) is swallowed. X-rays are then taken to evaluate the digestive organs.

urea – the nitrogen part of urine produced from the breakdown of protein.

urea breath test – test used to detect Helicobacter pylori (H. pylori) infection. The test measures breath samples for urease, an enzyme H. pylori
produces.

ureterocele – the portion of the ureter closest to the bladder becomes enlarged because the ureter opening is very tiny and obstructs urine outflow;
urine backs up in the ureter tube.

ureteroscope – an optical device which is inserted into the urethra and passed up through the bladder to the ureter; to inspect the opening of the
ureters.

ureters – two narrow tubes that carry urine from the kidneys to the bladder.

urethra – narrow channel through which urine passes from the bladder out of the body.

urethritis – an infection limited to the urethra.

urge incontinence – the inability to hold urine long enough to reach a restroom. It is often found in people who have conditions such as diabetes,
stroke, dementia, Parkinson’s disease, and multiple sclerosis, but may be an indication of other diseases or conditions that would also warrant medical attention.

urgent surgery (Also called emergency surgery.) – an operation performed immediately as a result of an urgent medical condition.

urinalysis – laboratory examination of urine for various cells and chemicals, such as red blood cells, white blood cells, infection, or excessive
protein.

urinary incontinence – the loss of bladder control.

urinary retention – the inability to empty the bladder.

urinary tract infection (UTI) – an infection that occurs in the urinary tract; often caused by bacteria such as Escherichia coli. A urinary tract
infection often causes frequent urination, pain, and burning when urinating, and blood in the urine.

urine flow study – a test in which the patient urinates into a special device that measures how quickly the urine is flowing. A reduced flow may suggest
benign prostatic hyperplasia(BPH).

urogenital – refers to the urinary and reproductive systems.

urology – the branch of medicine concerned with the urinary tract in both genders, and with the genital tract or reproductive system in the male.

urticaria (Also called hives.) – a condition in which red, itchy, and swollen areas appear on the skin – usually as an allergic reaction from eating
certain foods or taking certain medications.

urushiol – resin in poison ivy plants that causes an allergic skin reaction.

Usher’s syndrome – A hereditary disease that affects hearing and vision.

uterine wall – the wall of the uterus.

uterus (Also called the womb.) – a hollow, pear-shaped organ located in a woman’s lower abdomen, between the bladder and the rectum, that sheds its
lining each month during menstruation and in which a fertilized egg (ovum) becomes implanted and the fetus develops.

tachypnea – rapid breathing.

tamoxifen – a drug used in hormone therapy to treat breast cancer by blocking the effects of estrogen.

taste – sensation produced by a stimulus applied to the gustatory nerve endings in the tongue; the four tastes are salt, sour, sweet, and bitter; some
say there is a fifth taste described as savory.

taste buds – groups of cells located on the tongue that enable one to recognize different tastes.

taste disorder – inability to perceive different flavors.

telemetry unit – a small transmitter that is used to send information about the heart via radio transmission to healthcare professionals for evaluation.

temporal arteries – vessels located over the temples on each side of the head, that supply blood to part of the head.

temporomandibular joints (TMJ) – the two joints that connect the jaw to the skull.

tendon – the tough cords of tissue that connect muscles to bones.

tendonitis – an inflammation in a tendon or the tendon covering.

tenesmus – straining to have a bowel movement.

tennis elbow (Also called lateral epicondylitis.) – an injury to the tendons on the lateral portion of the elbow that bend the wrist backward away from
the palms of the hands.

testicular cancer – cancer that develops in a testicle.

testis – one of the pair of male gonads that produce semen; suspended in the scrotum by the spermatic cords.

testosterone – male sex hormone produced mostly by the testicles, which stimulates bone and muscle growth and the development of male sex
characteristics.

tetanus – an acute, sometimes fatal, disease of the central nervous system; caused by the toxin of the tetanus bacterium, which usually enters the body
through an open wound. The tetanus bacterium live in soil and manure, but also can be found in the human intestine and other places.

thalassemia – an inherited blood disorder in which the chains of the hemoglobin (a type of protein in red blood cells that carries oxygen to the tissues)
molecule are abnormal; alpha thalassemia results when a mutation occurs in the alpha chain, while beta thalassemia results when the mutation occurs in the beta chain; signs and symptoms of thalassemias vary from mild (little to no symptoms) to severe (life threatening).

thallium stress test – a study in which a radioactive substance is carried by the blood and its progress through the circulation of a specific body area
is followed by x-ray pictures.

thermal burns – burns due to external heat sources which raise the temperature of the skin and tissues and cause tissue cell death or charring. Hot
metals, scalding liquids, steam, and flames, when coming in contact with the skin, cause thermal burns.

thoracic spine – the 12 vertebrae between the cervical and lumbar spines that provide attachments for the ribs.

thoracotomy – surgery to view the lung that may be used to confirm cancer, or for chest trauma to detect the source of bleeding.

throat disorders – disorders or diseases of the larynx (voice box) or esophagus.

thrombolysis – the breaking up of a blood clot.

thrombolytic therapy – the use of a medication that dissolves blood clots.

thrombosis – excess clotting which obstructs veins (venous thrombosis) and arteries (arterial thrombosis).

thrombosis, deep-vein – formation of blood clots in veins deep inside the legs.

thrombus – a blood clot.

thyroid scan – uses a radioactive substance to create an image of the thyroid as it is functioning.

thyroplasty (Also known as laryngeal framework surgery.) – surgical technique to improve voice by altering the cartilages of the larynx.

thyroxine (T4) – a hormone secreted by the thyroid gland which regulates metabolism.

triiodothyronine (T3) – a hormone secreted by the thyroid gland which regulates metabolism.

tibia – shin bone or larger bone of the lower leg.

tinea versicolor – a common fungal skin infection characterized by white or light brown patches on the skin.

tinnitus – sensation of a ringing, roaring, or buzzing sound in the ears or head; often associated with various forms of hearing impairment.

tissue – group or layer of cells that together perform specific functions.

tissue expansion – a surgical procedure that involves inserting a balloon-like device (called an expander) under the skin. The expander then slowly
secretes liquid into the area to be repaired to actually stretch and expand the skin. This serves the function of "growing" extra skin to repair nearby lost or damaged skin.

tissue plasminogen activator (TPA) – a medication used to dissolve blood clots.

tomography – from the Greek words "to cut or section" (tomos) and "to write" (graphein), in nuclear medicine, it is a method of separating interference
from the area of interest by imaging a cut section of the object.

tongue – large muscle on the floor of the mouth that manipulates food for chewing and swallowing; the main organ of taste, and assists in forming speech
sounds.

tonometry – test to measure intraocular pressure for glaucoma.

topical chemotherapy – chemotherapy given as a cream or lotion placed on the skin to kill cancer cells.

torticollis (Also called wryneck.) – a twisting of the neck that causes the head to rotate and tilt on an angle.

total (or simple) mastectomy – surgery to remove the entire breast (including the nipple, areola, and most of the overlying skin) and may also remove
some of the lymph nodes under the arm, also called the axillary lymph glands.

total gastrectomy – complete removal of the stomach.

total hysterectomy – the surgical removal of the uterus, including the cervix; the fallopian tubes and the ovaries remain.

total hysterectomy with bilateral salpingo-oophorectomy – the entire uterus, fallopian tubes, and the ovaries are surgically removed.

Tourette’s syndrome – Neurological disorder characterized by tics and other movements such as eye blinks or facial twitches that cannot be controlled.

toxic epidermal necrolysis – a life-threatening skin disorder characterized by blistering and peeling of the top layer of skin.

toxoplasmosis – an infection caused by a parasite that can lead to serious illness or death in the fetus.

tracheoesophageal fistula (TEF) – condition that occurs when there is a gap between the upper and lower segments of the esophagus, and food and saliva
cannot pass through.

tracheostomy – surgical opening into the trachea (windpipe) to help someone breathe who has an obstruction or swelling in the larynx (voice box) or upper
throat.

trans fat – vegetable oil that has been treated with hydrogen in order to make it more solid and give it a longer shelf life.

transcutaneous electrical nerve stimulation (TENS) – a method of providing pain relief using electrical signals which are sent to the nerve endings.

transesophageal echocardiography (TEE) – a diagnostic test that is used to measure the sound waves that bounce off of the heart.

transferrin saturation test (TS) – a type of iron study (blood test) that measures the percentage of transferrin and other mobile, iron-binding proteins
saturated with iron.

transient ischemic attack (TIA) – a stroke-like event that lasts for a short period of time and is caused by a blocked blood vessel.

transplantation – replacing a damaged organ with one from a donor.

transrectal ultrasound of the prostate – a test using sound wave echoes to create an image of an organ or gland to visually inspect for abnormal
conditions such as gland enlargement, nodules, penetration of tumor through capsule of the gland, and/or invasion of seminal vesicles. It may also be used for guidance of needle biopsies of the prostate gland and guiding the nitrogen probes in cryosurgery.

transurethral hyperthermia – an investigative procedure that uses heat, usually provided by microwaves, to shrink the prostate.

transurethral incision of the prostate (TUIP) – a procedure that widens the urethra by making some small cuts in the bladder neck, where the urethra
joins the bladder, and in the prostate gland itself.

transurethral laser incision of the prostate (TULIP) – the use of laser through the urethra that melts the tissue.

transurethral resection of the prostate (TURP) – a surgical procedure by which portions of the prostate gland are removed through the penis.

transurethral surgery – surgery in which no external incision is needed. For prostate transurethral surgery, the surgeon reaches the prostate by
inserting an instrument through the urethra.

transvaginal ultrasound (Also called ultrasonography.) – an ultrasound test using a small instrument, called a transducer, that is placed in the vagina.

transverse colon – part of the colon that extends across the abdomen from right to left.

transverse frictions – deep massage technique used for tendon and ligament conditions.

transverse myelitis – inflammation and swelling along the spinal cord with motor or sensory nerve dysfunction.

trauma – a physical injury or wound caused by an external force of violence, which may cause death or permanent disability. Trauma is also used to
describe severe emotional or psychological shock or distress.

travel medicine – a specialized area of healthcare that focuses on the needs of travelers, particularly those who travel to other countries.

traveler’s diarrhea – a term used to describe diarrhea caused by infection with bacteria, protozoa, or viruses ingested by consuming food or water that
has been contaminated. Two life-threatening types of traveler’s diarrhea are caused by cholera and giardiasis.

tremor – a rhythmical shaking of a limb, head, mouth, tongue, or other part of the body.

tretinoin – a drug which is chemically related to vitamin A; used to treat acne and other scaly skin disorders.

trichomoniasis – very common type of vaginitis caused by a single-celled organism usually transmitted during sexual contact.

trichotillomania – a disorder characterized by recurrent, compulsive hair pulling.

tricuspid valve – the heart valve that controls blood flow from the right atrium into the right ventricle.

trigger finger – an irritation of the digital sheath that surrounds the flexor tendons of the finger. When the tendon sheath becomes thickened or
swollen, it pinches the tendon and prevents it from gliding smoothly. In some cases, the tendon catches and then suddenly releases as though a trigger were released.

trigger point – hypersensitive area or site in muscle or connective tissue, usually associated with myofascial pain syndromes.

triglyceride – a fat-like substance found in the blood.

trimester – a pregnancy is divided into phases, each lasting about three months.

trimester – period of three months.

tropical sprue – condition of unknown cause. Abnormalities in the lining of the small intestine prevent the body from absorbing food normally.

tubal ligation – surgical sterilization procedure in which the fallopian tubes are sealed or cut to prevent sperm from reaching an egg.

tube feeding (Also called enteral nutrition.) – a way to provide food through a tube placed in the nose, stomach, or small intestine. A tube in the nose
is called a nasogastric or nasoantral tube. A tube that goes through the skin into the stomach is called a gastrostomy or percutaneous endoscopic gastrostomy (PEG). A tube into the small intestine is called a jejunostomy or percutaneous endoscopic jejunostomy (PEJ) tube.

tuberculosis (TB) – an infectious disease that was once a major killer worldwide. The predominant TB organism is Mycobacterium tuberculosis (M.
tuberculosis). Spread person-to-person in airborne droplets caused by sneezing or coughing, the bacteria usually infects the lungs. However, due to improved nutrition, housing, sanitation, medical care, and the introduction of antibiotics this century, reported TB cases in the US have declined
dramatically.

tumor – an abnormal lump or mass of tissue. Tumors can be benign (non-cancerous) or malignant (cancerous).

tunica vaginalis – a thin pouch that holds the testes within the scrotum.

tunnel surgery (Also called percutaneous nephrolithotomy.) – a small cut is made in the patient’s back and a narrow tunnel is made through the skin to
the stone inside the kidney. The physician can remove the stone through this tunnel.

tympanometry – a test that allows for air and sound to be directed into the middle ear.

tympanoplasty – surgical repair of the eardrum (tympanic membrane) or bones of the middle ear.

type 1 diabetes – a condition in which the body’s immune system destroys the cells in the pancreas that produce insulin. Insulin allows glucose to enter
the cells of the body to provide energy. Persons with type 1diabetes must take daily insulin injections.

type 2 diabetes – a condition in which the body either makes too little insulin or cannot properly use the insulin it makes to convert blood glucose to
energy. Type 2 diabetes may be controlled with diet, exercise, and weight loss, or may require oral medications and/or insulin injections.

typhoid fever – a life-threatening bacterial infection caused by the bacterium Salmonella Typhi (S. Typhi); often transmitted by contaminated water,
food, or milk.

tyrosine – the amino acid from which dopamine is made.

safe sex – sex in a monogamous relationship where neither party is infected with a sexually transmitted disease or urinary tract infection is considered
to be "safe." However, many healthcare professionals believe there really is no such thing as "safe" sex, and the only way to be truly safe is to abstain as all forms of sexual contact carry some risk.

salicylic acid – a keratolytic drug (a drug that removes the outer layer of skin) that is used to treat various skin conditions.

saline solution – a solution containing sodium chloride.

saliva – mixture of water, protein, and salts that makes food easy to swallow and begins digestion.

salmonella – bacterium that may cause intestinal infection and diarrhea.

salmonella infections – diarrheal infections caused by the bacteria Salmonella. There are many kinds of Salmonella bacteria that cause diarrheal
illnesses in humans.

salpingectomy – surgical removal of one or both fallopian tubes.

salpingo-oophorectomy – surgery to remove the fallopian tubes and ovaries.

sarcoidosis – condition that causes small, fleshy swellings in the tissue around the organs, usually in the liver, lungs, and spleen.

saturated fat – fat that is found in foods from animal meats and skin, dairy products, and some vegetables.

scabies – an infestation of mites in the skin characterized by small pimples that itch.

scales – dead skin cells that look like flakes or dry skin.

scapula – shoulder blade.

scar – the body’s natural way of healing and replacing lost or damaged skin. A scar is usually composed of fibrous tissue. Scars may be formed for many
different reasons, including as a result of infections, surgery, injuries, or inflammation of tissue.

Schiller test – A diagnostic test in which the cervix is coated with an iodine solution to detect the presence of abnormal cells.

schizoid personality disorder – persons with this disorder are often cold, distant, introverted, and have an intense fear of intimacy and closeness.
Persons with schizoid personality disorder are often too absorbed in their own thinking and daydreaming that they exclude themselves from attachment with persons and reality.

schizophrenia – one of the most complex of all mental health disorders; involves a severe, chronic, and disabling disturbance of the brain.

schizotypal personality disorder – similar to schizoid personality disorder, persons with this disorder are often cold, distant, introverted, and have an
intense fear of intimacy and closeness. Yet, with schizotypal personality disorder, persons also exhibit disordered thinking, perception, and ineffective communication skills. Many symptoms of schizotypal personality disorder resemble schizophrenia, but are less mild and intrusive.

sciatica (Also called lumbar radiculopathy.) – a pain that originates along the sciatic nerve.

sclera – the white, visible portion of the eyeball. The muscles that move the eyeball are attached to the sclera.

scleroderma – a very serious disease of the body’s connective tissue that causes thickening and hardening of the skin.

sclerosing adenosis – a benign breast condition that involves excessive growth of tissues in the breast’s lobules, often resulting in breast pain.

sclerotherapy – method of stopping upper gastrointestinal (GI) bleeding. A needle is inserted through an endoscope to administer hardening agents to the
location that is bleeding.

scoliosis – a lateral, or sideways, curvature and rotation of the back bones (vertebrae), giving the appearance that the person is leaning to one side.

scotoma – an area of partial or complete loss of vision surrounded by an area of normal vision.

screening – checking for disease when there are no symptoms.

screening mammogram – an x-ray of the breast used to detect breast changes in women who have no signs of breast cancer.

scrotum – the bag of skin that holds the testicles.

seasonal affective disorder (SAD) – a mood disorder characterized by depression related to a certain season of the year – especially winter.

sebaceous glands – glands in the skin that secrete oil to the surface of the skin.

seborrheic keratosis – flesh-colored, yellow, brown, or black wart-like spots.

sebum – oily substance produced by sebaceous glands in the skin.

secondary tumor – a tumor that forms as a result of spread (metastasis) of cancer from the location where it originated.

secretin – hormone made in the duodenum that causes the stomach to produce pepsin, the liver to make bile, and the pancreas to produce a digestive juice.

segmental mastectomy – surgery to remove a portion of the breast.

segmentation – process by which muscles in the intestines move food and wastes through the body.

seizure – occurs when part(s) of the brain receives a burst of abnormal electrical signals that temporarily interrupts normal electrical brain function.

self-monitoring blood glucose – method for people with diabetes to find out how much glucose is in their blood.

sella turcica – bony structure that houses the pituitary gland.

sensorineural hearing loss – hearing loss caused by damage to the sensory cells and/or nerve fibers of the inner ear.

sepsis – the presence of bacteria, virus, fungus, or other organism in the blood or other tissues and the toxins associated with the invasion.

septal defect – a hole in the wall of the heart.

septoplasty – the surgical correction of defects and deformities of the nasal septum (the partition between the nostrils).

septum – the muscle wall that divides the heart chambers.

serology – the study of blood serum (the clear fluid that separates when blood clots).

serotonin – a chemical necessary for communication between nerve cells.

serum – a clear fluid that separates when blood clots.

sexually transmitted disease (STD) – infection spread through sexual intercourse and other intimate sexual contact.

shigellosis – infection with the bacterium Shigella, usually causing a high fever, acute diarrhea, and dehydration.

shin splints – damage to one of two groups of muscles along the shin bone that cause pain.

shock – impaired body function due to blood loss or a disturbance in the circulatory system.

short bowel syndrome (Also called short gut syndrome.) – problems related to absorbing nutrients after removal of part of the small intestine.

shunt – a connector to allow blood flow between two locations.

Shwachman’s syndrome – Digestive and respiratory disorder of children in which certain digestive enzymes are missing and white blood cells are few.

sialorrhea – drooling.

sickle cell anemia – an inherited blood disorder characterized by defective hemoglobin.

sigmoid colon – lower part of the colon that empties into the rectum.

sigmoidoscopy – a diagnostic procedure that allows the physician to examine the inside of a portion of the large intestine, and is helpful in identifying
the causes of diarrhea, abdominal pain, constipation, abnormal growths, and bleeding. A short, flexible, lighted tube, called a sigmoidoscope, is inserted into the intestine through the rectum. The scope blows air into the intestine to inflate it and make viewing the inside easier.

sign language – language of hand shapes, facial expressions, and movements used as a form of communication.

silent ischemia – ischemia not accompanied by chest pain.

simple mastectomy – surgical removal of the breast and possibly a few of the axillary lymph nodes close to the breast.

sinus node – the cells that produce the electrical impulses that cause the heart to contract.

sinuses – air cavities within the facial bones, lined by mucous membranes similar to those in other parts of the airways.

sinusitis – inflammation of the membranes lining the facial sinuses, often caused by bacterial or viral infection, or allergic reaction.

skilled nursing facility (SNF) – an out-of-home care option for elderly persons who require continuous nursing care. SNFs can provide extensive care
services, such as intravenous feedings, blood pressure monitoring, medication injections, and care for patients on ventilators.

skin (cutaneous) diphtheria – one type of diphtheria; the symptoms are usually milder and may include yellow spots or sores (similar to impetigo) on the
skin.

skin cancer – a malignant tumor that grows in the skin cells.

skin grafts – a skin graft may be used to cover skin that has been damaged and/or is missing. This surgical procedure involves removing healthy portions
of skin from one part of the body to restore normal appearance and/or function to another portion of the same body. The location where the skin is removed is called the donor site. There are various types of skin grafts that may be utilized, depending upon the size and location of needed skin.

skin tags – soft, small, flesh-colored skin flaps on the neck, armpits, or groin.

small intestine – the section of the digestive tract between the stomach and the large intestine. Most of digestion occurs here as nutrients are absorbed
from food.

smallpox – a highly contagious disease caused by a type of poxvirus; symptoms usually include a fever and a blistery-like rash.

smell – to perceive odor or scent through stimuli affecting the olfactory nerves.

smell disorder – inability to perceive odors that may be temporary or permanent.

smooth muscle – muscle that performs automatic tasks, such as constricting blood vessels.

social phobia – an anxiety disorder in which a person has significant anxiety and discomfort related to a fear of being embarrassed, humiliated, or
scorned by others in social or performance situations.

soft tissues – the ligaments, tendons, and muscles in the musculoskeletal system.

somatosensory – refers to sensory signals from all tissues of the body including skin, viscera, muscles, and joints.

somatostatin – hormone in the pancreas that helps tell the body when to make the hormones insulin, glucagon, gastrin, secretin, and renin.

sound vocalization – ability to produce voice.

spasm – a condition in which a muscle or group of muscles involuntarily contract.

spasmodic dysphonia – momentary disruption of voice caused by involuntary movements of one or more muscles of the larynx (voice box).

spasms – muscle movements such as those in the colon that cause pain, cramps, and diarrhea.

spasticity – increased muscle tone that results in a tightening and shortening of a muscle.

specific language impairment (SLI) – difficulty with the organized symbol-system communication in the absence of problems such as mental retardation,
hearing loss, or emotional disorders.

specific phobia – a type of phobia characterized by extreme fear of an object or situation that is not harmful under general conditions.

speech – making definite vocal sounds that form words to express thoughts and ideas.

speech disorder – defect or abnormality that prevents an individual from communicating by means of spoken words.

speech processor – part of a cochlear implant that converts speech sounds into electrical impulses to stimulate the auditory nerve.

speech-language pathologist – health professional trained to evaluate and treat people who have voice, speech, language, or swallowing disorders,
including hearing impairment, that affect their ability to communicate.

sperm disorders – problems with the production and maturation of sperm; the single most common cause of male infertility. Sperm may be immature,
abnormally shaped, unable to move properly, or, normal sperm may be produced in abnormally low numbers (oligospermia).

SPF – Sun Protection Factor.

sphincter – ring-like band of muscle that opens and closes an opening in the body.

sphincter muscles – circular muscles that help keep urine from leaking by closing tightly like a rubber band around the opening of the bladder.

sphincter of Oddi – muscle between the common bile duct and pancreatic ducts.

sphincterotomy – a procedure to open the muscle sphincter – a ring of muscle around a natural opening that acts like a valve – wide enough so stones can
pass into the intestine.

sphygmomanometer – the instrument used to measure blood pressure.

spider angioma – a bright red mark with a distinct dark spot in the skin.

spinal anesthesia – injection of an anesthetic into the area around the spinal cord to block pain sensation during surgery.

spinal cord – a bundle of nerves that carries messages between the brain and the rest of the body.

spinal instability – increased motion between vertebra, usually resulting from an injury; pain typically feels like tingling in the neck or arms.

spinal stenosis – narrowing of the nerve openings either around the spinal cord or nerve roots that can cause symptoms similar to a pinched nerve; pain
is described either as an aching or an electrical feeling down the arm.

spinal tap (Also called lumbar puncture.) – a special needle is placed into the lower back, into the spinal canal. This is the area around the spinal
cord. The pressure in the spinal canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF) can be removed and sent for testing to determine if there is an infection or other problems. CSF is the fluid that bathes the brain and spinal cord.

spine – a column in the body consisting of 33 vertebrae.

spirogram – a record of the amounts of air being moved in and out of the lungs.

spirometer – an instrument that measures the amount of air moved in and out of the lungs (the amount of inhaled and exhaled air).

spirometry – a pulmonary test of the lungs using a spirometer.

spleen – organ that cleans blood and makes white blood cells.

splenectomy – surgical removal of the spleen.

splenic flexure syndrome – condition that occurs when air or gas collects in the upper parts of the colon.

splints – a device for preventing movement of a joint or holding in place any part of the body.

spondylitis – inflammation of the spine.

spondylolisthesis – forward displacement of one vertebra on its lower neighbor.

spondylosis – a degenerative process of the cervical spine that causes narrowing of the spinal canal and neural foramina, and produces compression of the
spinal cord and nerve roots.

sporadic – occurring by chance.

sprain – a partial or complete tear of a ligament.

sputum (Also called phlegm.) – mucus from the lungs.

squamous cell cancer – a slow-growing cancer in cells in the top layer of the skin.

squamous cell carcinoma – a form of skin cancer that affects about 20 percent of patients with skin cancer. This highly treatable cancer is characterized
by red, scaly skin that becomes an open sore.

squamous cells (Also called keratinocytes.) – the primary cell types found in the epidermis, the outer layer of skin.

squamous intraepithelial lesion (SIL) – a term used to classify the degree of precancerous change in cells of the cervix in a condition called cervical
dysplasia.

stage – the extent of a cancer; whether the disease has spread from the original site to other parts of the body.

staging – an evaluation of the extent of disease that provides the basis for making treatment recommendations.

steatorrhea – condition in which the body cannot absorb fat.

stem cell transplantation – removing stem cells from the patient’s or a donor’s bone marrow and re-infusing them into the patient to help produce healthy
blood cells; a method of replacing stem cells which are destroyed by cancer treatment.

stem cells – the blood cells that produce other blood cells. It is the stem cells that are needed in bone marrow transplantation.

stenosis – the narrowing or constriction of a blood vessel or valve in the heart.

stent – a device implanted in a vessel used to help keep it open.

stereopsis – ability to perceive three-dimensional depth.

sternum – the breastbone.

stethoscope – the instrument used to listen to the heart and other sounds in the body.

stirrups – technique of ankle strapping using rigid tape placed on the ankle, medial to lateral adhering to the undersurface of the heel, mimicking a
stirrup.

stoma – a surgically created opening in an organ.

stomach – organ between the esophagus and the small intestine. The stomach is where digestion of protein begins.

stomach ulcer (Also called a gastric ulcer.) – open sore in the stomach lining.

stool (Also called feces.) – solid wastes that pass through the rectum as bowel movements. Stools are undigested foods, bacteria, mucus, and dead cells.

stork bite (Also called salmon patch.) – small pink or red patches often found on a baby’s eyelids, between the eyes, upper lip, and back of the neck.

straight leg raise (SLR) – technique for measuring sciatic nerve mobility and/or hamstring length.

strain – a partial or complete tear of a muscle or tendon.

strawberry hemangioma – a bright or dark red, raised or swollen, bumpy area on the skin of a baby or child.

streptokinase – a clot-dissolving medication.

stress – mental or physical tension that results from physical, emotional, or chemical causes.

stress fractures – weak spots or small cracks in the bone caused by continuous overuse.

stress incontinence – the most common type of incontinence that involves the leakage of urine during exercise, coughing, sneezing, laughing, lifting
heavy objects, or other body movements that put pressure on the bladder.

stress ulcer – upper gastrointestinal (GI) ulcer from physical injury such as surgery, major burns, or critical head injury.

striatum – part of the basal ganglia; a large cluster of nerve cells, consisting of the caudate nucleus and the putamen, that controls movement, balance,
and walking; the neurons of the striatum require dopamine to function.

stricture (Also called stenosis.) – abnormal narrowing of a body opening.

stroke (Also called brain attack.) – occurs when brain cells die because of inadequate blood flow to the brain.

stuttering – frequent repetition of words or parts of words that disrupts the smooth flow of speech.

subarachnoid hemorrhage – a stroke that occurs when a blood vessel on the surface of the brain ruptures and bleeds into the space between the brain and
the skull (but not into the brain itself).

subchondral tissue – the smooth tissue at the ends of bones, which is covered with another type of tissue called cartilage.

subcutis (Also called subcutaneous layer.) – the deepest layer of skin.

substantia nigra – a small area of the brain containing a cluster of black-pigmented nerve cells that produce dopamine, which is then transmitted to the
striatum.

subtotal or partial gastrectomy – surgical removal of a portion of the stomach.

sudden deafness – loss of hearing that occurs quickly from such causes as explosion, a viral infection, or the use of some drugs.

sudden death – death that occurs unexpectedly or immediately after onset of symptoms.

sudden infant death syndrome (SIDS) – unexplained, sudden death of an infant up to 1 year of age.

suicide – the intentional taking of one’s own life.

sunburn – a visible reaction of the skin to overexposure to the sun’s invisible ultraviolet (UV) rays.

sunscreen – a product that protects the skin again sunburns by blocking the penetration of the sun’s ultraviolet (UV) rays.

superior vena cava – the large vein that returns blood to the heart from the head and arms.

suprarenal glands – another name for the adrenal glands.

surgery – operation to remove or repair a part of the body, or to determine if disease is present.

suspensory ligament of lens – a series of fibers that connect the ciliary body of the eye with the lens, holding it in place.

sustention (postural) tremor – a tremor of a limb that increases when the limb is stretched.

swallowing disorders – any of a group of problems that interfere with the transfer of food from the mouth to the stomach.

synapse – a tiny gap between the ends of nerve fibers across which nerve impulses pass from one neuron to another; at the synapse, an impulse causes the
release of a neurotransmitter, which diffuses across the gap and triggers an electrical impulse in the next neuron.

syncope – light-headedness or fainting caused by insufficient blood supply to the brain.

syndactyly – a congenital problem characterized by a union of fingers or toes.

syndromic hearing impairment – hearing loss or deafness that is inherited or passed through generations of a family.

synovial fluid – a clear, sticky fluid that is released by the synovial membrane and acts as a lubricant for joints and tendons.

synovial membrane – a tissue that lines and seals the joint.

synovitis – inflammation of the synovial membrane, the tissue that lines and protects the joint.

synovium – a fibrous envelope that produces a fluid to help to reduce friction and wear in a joint.

syphilis – a sexually transmitted disease caused by Treponema pallidum bacteria. The initial symptom of syphilis is a painless open sore that usually
appears on the penis or around or in the vagina. If untreated, syphilis may go on to more advanced stages, including a transient rash and, eventually, serious involvement of the heart and central nervous system.

syrup of ipecac – an emetic made from the dried root of a plant called ipecacuanha, which is grown in Brazil. An emetic is an agent that causes vomiting.

systemic – disease or symptoms that affect many different parts of the body.

systemic chemotherapy – chemotherapy taken by pill or needle injection into a vein or muscle.

systemic juvenile rheumatoid arthritis – a form of juvenile rheumatoid arthritis that affects joints and, sometimes, internal organs.

systemic lupus erythematosus (Also called SLE or lupus.) – a very serious, chronic, autoimmune disorder characterized by periodic episodes of
inflammation of and damage to the joints, tendons, other connective tissues, and organs, including the heart, lungs, blood vessels, brain, kidneys, and skin.

systemic treatment or therapy – treatment or therapy that reaches and affects cells throughout the body.

systolic blood pressure – the highest pressure to which blood pressure rises with the contraction of the ventricles.

radial keratotomy – a surgical procedure in which incisions are made into the epithelium of the cornea to correct refractive errors.

radiation – use of high-energy radiation from x-rays, neutrons, and other sources to kill cancer cells and shrink tumors.

radiation colitis – damage to the colon from radiation therapy.

radiation enteritis – damage to the small intestine from radiation therapy.

radiation therapy (Also called radiotherapy.) – treatment with high-energy rays (such as x-rays or gamma rays) to kill cancer cells; may be by external
radiation or by internal radiation from radioactive materials placed directly in or near the tumor.

radical mastectomy – surgery to remove the entire breast (including the nipple, areola, and overlying skin), the lymph nodes under the arm, also called
the axillary lymph glands, and the chest muscles.

radical prostatectomy – surgery to remove the prostate along with the two seminal vesicle glands attached to the prostate.

radical retropubic prostatectomy – an operation to remove the entire prostate gland and seminal vesicles through the lower abdomen.

radioisotope – a radioactive material injected into the body so that a nuclear scanner can make pictures.

radioisotope scan – a procedure that uses radioactive substances introduced into the body to create an image.

radioisotopes – materials that produce radiation.

radiologist – a physician specializing in the medical field of radiology.

radionuclide bone scan – a nuclear imaging technique that uses a very small amount of radioactive material, which is injected into the patient’s
bloodstream to be detected by a scanner. This test shows blood flow to the bone and cell activity within the bone.

radionuclide scan – an imaging scan in which a small amount of radioactive substance is injected into the vein. A machine measures levels of
radioactivity in certain organs, thereby detecting any abnormal areas or tumors.

radionuclide ventriculography – a diagnostic procedure used to determine the shape and size of the heart’s chambers.

radiopharmaceutical (Also called a tracer or radionuclide.) – basic radioactively-tagged compound necessary to produce a nuclear medicine image.

radius – the shorter of the two bones of the forearm.

radon – a colorless, naturally-occurring, radioactive, inert gas formed by radioactive decay of radium atoms in soil or rocks.

Rancho scales – Levels of a patient’s response to external stimuli and the environment following a brain injury.

range of motion – measurement of the extent to which a joint can go through all of its normal spectrum of movements.

rape – forced or manipulated nonconsensual sexual contact, including vaginal or anal intercourse, oral sex, or penetration with an object.

RAST (RadioAllergoSorbent Test, a trademark of Pharmacia Diagnostics) – a laboratory test used to detect IgE antibodies to specific allergens. A RAST
requires a blood sample, which is sent to a medical laboratory where tests are done with specific foods to determine whether the patient has IgE antibodies to that food.

reactive arthritis (Also called Reiter’s syndrome.) – a type of arthritis that occurs as a reaction to an infection.

recommended dietary allowance (RDA) – recommendations for daily intake of specific nutrients for groups of healthy individuals set by the Food and
Nutrition Board of the National Research Council of the National Academy of Science.

reconstructive plastic surgery – one type of plastic surgery that is performed on abnormal structures of the body that may be caused by trauma,
infection, developmental abnormalities, congenital defects, disease, and/or tumors. This type of surgery is usually performed to improve function, but may also be performed to approximate a normal appearance.

rectal manometry – test that uses a thin tube and balloon to measure pressure and movements of the rectal and anal sphincter muscles.

rectal prolapse – condition in which the rectum slips so that it protrudes from the anus.

rectal ultrasound – a test in which a probe is inserted in the rectum and directs sound waves at the prostate. The patterns of the sound waves form an
image of the prostate gland on a screen.

rectocele – condition in which weakening of the lower vaginal wall causes the rectum to bulge into the vagina.

rectum – lower end of the large intestine, leading to the anus.

recur – to occur again; reappearance of cancer cells at the same site or in another location.

red blood cells (Also called RBCs or erythrocytes.) – blood cells that transport oxygen to all the tissues in the body.

reflux (Also called regurgitation.) – condition that occurs when gastric juices or small amounts of food from the stomach flow back into the esophagus
and mouth.

reflux esophagitis – irritation of the esophagus because stomach contents flow back into the esophagus.

refractive error – the degree to which light reaches the back of the eye – myopia, hyperopia, astigmatism.

regional anesthetic – an anesthetic used to numb a portion of the body.

regurgitation – backward flow of blood caused by a defective heart valve.

rehabilitation – the process of helping a person achieve the highest level of function, independence, and quality of life possible. From the Latin
"habilitas," which means "to make able."

renal – pertains to kidneys.

renal angiography (Also called renal arteriography.) – a series of x-rays of the renal blood vessels with the injection of a contrast dye into a
catheter, which is placed into the blood vessels of the kidney; to detect any signs of blockage or abnormalities affecting the blood supply to the kidneys.

renal ultrasound – a non-invasive test in which a transducer is passed over the kidney producing sound waves which bounce off of the kidney, transmitting
a picture of the organ on a video screen. The test is used to determine the size and shape of the kidney, and to detect a mass, kidney stone, cyst, or other obstruction or abnormalities.

required surgery – an operation which is necessary to continue quality of life. Required surgery may not have to be done immediately, like emergency
surgery.

residential care facility (RCF) – an out-of-home care option for elderly persons who are no longer able to live alone and independently, but do not
require skilled nursing care. RCFs typically provide assistance with personal hygiene, grooming, and other activities of daily living, as well as recreational and social services.

respiration – gas exchange from air to the blood and from the blood to the body cells.

respiratory diphtheria – when a person is infected with diphtheria, the bacterium usually multiplies in the throat, leading to the respiratory version of
diphtheria. A membrane may form over the throat and tonsils, causing a sore throat. Other common symptoms of respiratory diphtheria may include: breathing difficulty, a husky voice, enlarged lymph glands, and an increased heart rate.

respiratory system – the group of organs responsible for carrying oxygen from the air to the bloodstream, and for expelling carbon dioxide.

resting tremor – a tremor of a limb that increases when the limb is at rest.

retching – dry vomiting.

retina – the light-sensitive nerve layer that lines the back of the eye. The retina sense light and creates impulses that are sent through the optic
nerve to the brain.

retinal detachment – separation of the retina from the epithelium layer and from blood supply.

retinopathy – diabetic eye disease.

retrolisthesis – posterior slippage of one vertebra onto another.

retropulsion – the tendency to step backwards if bumped from the front or upon initiating walking; usually seen in patients who tend to lean backwards
because of problems with balance.

Reye syndrome – A potentially fatal disease that causes severe problems with the brain and other organs. Although the exact cause of the disease is not
known, there has been an association with giving aspirin to children and developing the disease. It is now advised not to give aspirin to children during illnesses, unless prescribed by your child’s physician.

rheumatic fever – a childhood disease that may damage the heart valves or the outer lining of the heart.

rheumatoid arthritis – an inflammatory disease that involves the lining of the joint (synovium). The inflammation often affects the joints of the hands
and the feet and tends to occur equally on both sides of the body.

rheumatoid factor – special kind of antibody often found in people with rheumatoid arthritis.

rhinitis – an inflammation of the mucous membrane that lines the nose, often due to an allergy to pollen, dust, or other airborne substances, which
causes sneezing, itching, runny nose, and nasal congestion.

rhinoplasty – the surgical repair of a defect of the nose, including reshaping or resizing the nose. Rhinoplasty may be performed to change the size of
the nose, change the shape of the nose, narrow the nostrils, and/or change the angle between the nose and lips. Rhinoplasty involves the resculpting of the bone and cartilage.

rhytidectomy (Also called facelift.) – a surgical procedure that involves the removal of excess facial fat, the tightening of facial muscles, and the
stretching of facial skin – to approximate a smoother, firmer appearance. The procedure takes place on either the face, neck, or both.

R.I.C.E. (Rest, Ice, Compression, and Elevation) – treatment plan for acute injury to prevent inflammatory processes from becoming uncontrolled and to
speed up the recovery process by eliminating swelling; acute injury management.

rigidity – increased resistance to the passive movement of a limb.

ringworm – a fungal skin infection characterized by ring-shaped, red, scaly, or blistery patches.

risk factor – activity or factor that may increase the chance of developing a disease.

rooting – when a newborn turns his/her head toward touch near the mouth.

rosacea – a common skin condition characterized by redness, pimples, and broken blood vessels.

rotator cuff – muscles and tendons that form a cuff over the shoulder joint and attach the scapula to the bone in the upper arm (humerus); major function
is to control and produce rotation of the shoulder.

round window – membrane separating the middle ear and inner ear.

rubella (Also called German measles.) – an acute viral infection that causes a mild illness in children and slightly more severe illness in adults. The
disease is spread person-to-person through airborne particles and takes two to three weeks to incubate.

rupture – break or tear in any organ or soft tissue.

quadriceps – a large, four-part muscle at the front of the thigh that facilitates leg extension.

quadriplegia – loss of movement and sensation in all four limbs.