Oregano Cures - Medicine and Health Glossary "S"

Term	Synonyms	Definition
Saccharides		A group of carbohydrates, including sugars and starches.
Saccharin		A man-made sweetener that people use in place of sugar because it has no calories.
Sacroiliac joint		The juncture between the sacrum and the ilium.
Sacroiliitis		An inflammation of the sacroiliac joints, which causes pain in the lower body.
Sacrum		Triangular bone at the base of the spine just above the coccyx. Composed of five fused vertebrae, it forms the back of the bony pelvis.
SADS	SAD	See Seasonal affective disorder syndrome.
Safe sex		Measures taken to reduce the risk of acquiring a sexually transmitted disease, such as the use of a condom.
Saline		Pertaining to salt.
Saliva		Fluid secreted by the salivary and mucous glands of the mouth that moistens food and begins the process of digestion.
Salivary glands		A group of glands that secrete saliva into the mouth.
Salmonella		A group of bacteria; includes a species that causes food poisoning and another responsible for typhoid fever.
Salmonellosis		An infection by salmonella bacteria.
Salpingectomy		The surgical removal of one or both fallopian tubes.
Salpingitis		An inflammation of a fallopian tube.
Salpingography		The X-ray examination of the fallopian tubes.
Salpingolysis		The removal of abnormal scar tissue between a fallopian tube and nearby tissue.
Salpingo-oophorectomy		The surgical removal of one or both of the fallopian tubes and one or both of the ovaries.
Salpingostomy		The surgical opening of a fallopian tube for drainage or removal of an obstruction.
Saphenous vein		Large vein in the leg.
Saponin(s)		Chemicals from plants, frequently associated with adverse or toxic reactions. They uniformly produce soapy lathers.
Sarcoidosis		A rare disease with no known cause that leads to inflammation in tissues throughout the body, including the lymph nodes, lungs, liver, skin, and eyes.
Sarcoma		A malignant tumor originating in connective tissue or bone.
SARS	Severe Acute Respiratory Syndrome	A highly contagious and sometimes fatal respiratory ilness.
Saturated fat		Fats that contain the maximum amount of hydrogen possible, such as those found in meats and dairy products; can contribute to coronary heart disease and the development of some cancers.
Saturday night palsy		The temporary paralysis of the arm after extended pressure on a nerve in the armpit.
Scabies		A skin disorder caused by a mite that causes redness, itching and swelling of involved area.
Scan		A test using a radioactive substance to locate tumors.
Scapula		Shoulder blade.
Scarlet fever		An infectious childhood disease, caused by a streptococcus bacteria, that leads to a sore throat, fever, and rash.
Scar tissue		A mark left on damaged tissue after it has healed. It can form on the skin or on internal wounds.
Schistosomiasis		An infestation by a parasitic blood worm that can damage the liver, bladder, and intestines.
Schizophrenia		A group of mental disorders characterized by abnormal thoughts, moods, and actions; sufferers have a distorted sense of reality, and a split personality (thoughts do not logically fit together).
Scholionophobia		The fear of school.
Schönlein-Henoch purpura		An inflammation and leakage of blood vessels, causing a rash.
Sciatica		Pain along the sciatic nerve, which runs down the length of the leg to the foot; usually caused by pressure on the nerve due to disk prolapse or a tumor, abscess, or blood clot.
Sciatic nerve		The largest nerve in the body provides sensory and motor function to the lower extremeties.
Sciophobia		The fear of shadows.
Sclera		The white, fibrous outer membrane of the eyeball.
Scleroderma		An immune system disorder of varying degree that can affect many areas of the body.
Sclerosing adenosis		A benign breast disease that involves the excessive growth of tissues in the breast's lobules.
Sclerosis		Hardening or thickening of an organ or tissue, usually due to abnormal growth of fibrous tissue.
Sclerotherapy		The treatment of varicose veins by injection of a solution that destroys them.
Scoliosis		A condition in which the spine curves to one side and usually curves toward the opposite side in another section to compensate, producing a characteristic S shape.
Screening		Tests or observations applied to a large cohort of individuals to identify disease or risk of disease.
Scrofula		The former term for tuberculosis.
Scrotum		The pouch that holds the testicles.
Scurvy		A disease caused by a lack of vitamin C, characterized by weakness, bleeding and pain in joints and muscles, bleeding gums, and abnormal bone and tooth growth.
Seasonal affective disorder syndrome		A type of depression that seems to be linked to shorter periods of daylight during the fall and winter.
Sebaceous cyst		A swelling that occurs under the skin, most commonly on the scalp, face, ears, and genitals; although usually harmless, can grow very large and become painful if infected.
Sebaceous glands		Oil glands of the skin.
Seborrhoea		An excessive oiliness of the face and scalp.
Seborrheic keratosis		A benign skin lesion resulting from excessive growth of the top layer of skin cells. It usually is found in persons over 30 years old and may be few or numerous.
Sebum		Fatty substance secreted by sebaceous glands to lubricate the skin.
Secondary		A term used to describe a disease or disorder that follows or is caused by another one.
Secondary diabetes		Diabetes resulting from another disease or taking certain drugs or chemicals.
Secrete		To produce and release, such as when beta cells make insulin and then release it into the blood for the body's cells to use in converting glucose into energy.
Secretion		The process of producing a substance by a gland; also, the substance produced.
Sedatives		A group of substances that have a calming effect; used to treat anxiety and pain, bring on sleep, and help relax a person before surgery.
Sedentary		Lacking exercise; inactive.
Sedimentation rate		A sedimentation rate, or "sed rate", is a blood test that detects and monitors inflammation activity. It is measured by recording the rate at which red blood cells (RBCs) sediment in a tube over time. It increases (the RBCs sediment faster) with more inflammation.
Segmental transplantation		A surgical procedure in which a part of a pancreas that contains insulin-producing cells is placed in a person whose pancreas has stopped making insulin.
Seizure		sudden attack of epileptic convulsion. It is a result of involuntary electrical activity in the brain. It can be associated with uncontrolled motor (movement) or sensory system action. Accordingly, a patient suffering a seizure may experience uncontrollable body movements, unusual smells or tastes and have loss of consciousness (awareness of surroundings).
Selenium		An element needed by the body only in very small amounts that helps maintain tissue elasticity.
Self blood glucose monitoring	Home blood glucose monitoring	A process by which blood sugars can be determined at home by pricking the finger, putting a drop of blood on a chemically treated test strip, and comparing the color changes to a chart.
Semen		Thick, whitish fluid containing sperm that is discharged through the penis during ejaculation.
Semen analysis		A procedure in which a semen sample is examined to determine the amount of sperm present, along with their shape and ability to move; commonly used in the treatment of male infertility.
Seminal vesicles		Sac-like structures in the male, located near the prostate gland, which store fluid that is part of semen.
Seminiferous tubules		The coiled tubes inside of the testicle that are the site of sperm production
Seminoma		One type of malignant tumor of the testicle.
Senescence		Process of aging.
Senile plaques		The abnormal deposits of a protein called amyloid in the brain; characteristic of Alzheimer disease.
Sensorineural hearing loss		Deafness caused by damage to the inner ear or the nerve that conducts signals from the ear to the brain.
Sensory nerve		The nerves that carry information about the body’s senses toward the brain.
Sensory organ		An organ that receives and relays information about the body’s senses to the brain.
Sepsis		Infection with disease-causing microorganisms or other toxins in the bloodstream.
Septal defect		Hole in the wall separating the two atria or the two ventricles.
Septic arthritis		Joint inflammation caused by a bacterial infection.
Septicemia		Presence of disease-causing bacteria or their toxins in the blood; also known as blood poisoning.
Septum		A wall dividing two cavities or compartments.
Septic shock		A life-threatening condition in which tissues become damaged and blood pressure drops due to bacteria multiplying and producing poisons in the blood.
Serotonin		A chemical that transmits nerve impulses in the brain, causes blood vessels to constrict (narrow) at sites of bleeding, and stimulates smooth muscle movement in the intestines.
Serum		The clear liquid left after the blood coagulates and forms a clot.
Sessile		Without a stalk.
Sex chromosomes		The X and Y chromosomes that determine a person’s gender; women normally have two X chromosomes and men normally have one X and one Y.
Sex hormones		The hormones responsible for producing sex characteristics and controlling sexual functions.
Sex-linked disorder		A disorder that is caused by genes located on the sex chromosomes.
Sexually transmitted disease		Infections that are most commonly spread through sexual intercourse or genital contact.
SGOT	Serum Glutamic Oxaloacetic Transaminase	A blood test to measure liver function or detect damage to the heart muscle.
Shigellosis		A bacterial infection of the intestines, causing abdominal pain and diarrhea.
Shingles		A painful rash due to viral infection of nerve tissue; herpes zoster.
Shin splints		Pain and tenderness experienced in the lower leg as a result of damage or strain to leg muscles and tendons; usually caused by exercise.
Shock		A severe disturbance of the circulatory system's ability to provide adequate blood to the tissues. May result from many causes such as trauma, bleeding, infection with sepsis and allergic reactions.
Shunt		A passage that diverts blood flow from one route to another. May occur naturally or be created surgically.
Sialogogue		A substance that stimulates the secreation of saliva.
Sickle cell anemia		A genetic disorder in which the red blood cells are abnormal and deformed, causing anemia (reduced ability to transport oxygen in the blood) and clogging of blood vessels; bouts of fever, headache, and weakness result.
Sickle cell disease		An inherited disorder in people of African descent that leads to abnormal red blood cells and anemia.
Sickle cell trait		A less serious form of sickle cell anemia.
Sickled cells		In children with sickle cell disease, hemoglobin molecules in red blood cells stick to one another and cause the red cells to become crescent or sickle shaped. Sickled cells cannot pass easily through tiny blood vessels.
Sick sinus syndrome		Failure of the sinus node to properly regulate the heartbeat. It may result in periods of either fast or slow heartbeat.
Side effects		Undesirable effect of a medication or other treatment.
SIDS		See Sudden infant death syndrome.
Sigmoidoscope		A lighted instrument used to view the inside of the lower colon.
Sigmoidoscopy		An examination of the rectum and the lowest part of the large intestine using a flexible viewing tube inserted through the anus.
Silent carriers		When both parents carry defective, recessive genes (genes determine hereditary characteristics).
Silent ischemia		Insufficient supply of blood and oxygen to the heart muscle without symptoms.
Silicone		A group of compounds of silicon and oxygen; commonly used as implants in cosmetic surgery because they resist body fluids and are not rejected by the body.
Silicosis		A respiratory disease caused by inhalation of dust containing the mineral silica.
Simulation		A process involving special x-ray pictures that are used to plan radiation treatment so that the area to be treated is precisely located and marked for treatment.
Single blind		Characteristic of a controlled experiment in which patients do not know which of several treatments they are receiving, thus preventing personal bias from influencing their reactions and study results. In double-blind studies, neither the patient nor the attending physician knows whether the patient is getting one or another drug or dose. In either case, the treatment can be quickly identified, if necessary, by a special code.
Single photon emission computed tomography		An imaging technique in which a radioactive substance is introduced into the body and the radiation emitted by the substance is detected by a camera and is transformed into cross-sectional images by a computer.
Sinoatrial node	Sinus node	The structure that regulates the heartbeat; a natural "pacemaker".
Sinus bradycardia		A regular heart rate of less than 60 beats per minute.
Sinuses		Empty spaces or cavities usually within a bony structure.
Sinusitis		An inflammation of the lining of the cavities in the bone surrounding the nose (the sinuses), usually as a result of a bacterial infection spreading from the nose.
Sinus rhythm		A normal heart rhythm.
Sinus tachycardia		A regular heart rate of over 100 beats per minute.
Sitz bath		A shallow bath; a therapeutic immersion of the thighs and hips in warm water, sometimes with another substance in solution.
Sjögren's syndrome		A condition characterized by dryness of the eyes, mouth, and vagina that tends to occur along with certain disorders of the immune system.
Skeleton		The skeleton is composed of bones and is the framework of the body
Skin graft		A method of treating damaged or lost skin in which a piece of skin is taken from another area of the body and transplanted in a damaged or missing section.
Skin patch		A sticky patch attached to the surface of the skin that releases drugs into the bloodstream.
Skin patch test		A diagnostic test in which different allergens are taped to the skin to determine which causes an allergic reaction.
Skin prick test		A test performed to determine a person’s sensitivity to a certain allergen by applying it to a small needle and using that needle to pierce the skin.
Skull		The bones that form the framework of the head and enclose and protect the brain and other sensory organs.
Sleep apnea		A condition in which breathing stops for very short periods of time during sleep.
Sleeping sickness		An infectious disease in Africa spread by the bite of a tsetse fly that causes a fever and weakness .
Slipped disk		The common term for disk prolapse.
Small cell carcinoma		The most serious form of lung cancer.
Small cell lung cancer		A type of lung cancer in which the cells are small and round. Also called oat cell lung cancer.
Small intestine		The long tube running from the stomach to the large intestine that is involved in digestion of foods and absorption of nutrients.
Smallpox		A highly contagious and often fatal viral infection that has been completely eradicated by immunization.
Smear		A sample of cells spread across a glass slide to be examined through a microscope.
Smoldering leukemia	Myelodysplastic syndrome, Preleukemia	A condition in which the bone marrow does not function normally. It does not produce enough blood cells. This condition may progress and become acute leukemia.
Sodium	Na	A mineral that is essential in maintaining the fluid balance of the body. Table salt (sodium chloride) is nearly half sodium.
Sodium bicarbonate		A substance used as an antacid.
Soft tissue sarcoma		A sarcoma that begins in the muscle, fat, fibrous tissue, blood vessels, or other supporting tissue of the body. Not a type of bone cancer.
Solar plexus		The largest network of nerves in the body, located behind the stomach.
Somatic		Pertaining to the body.
Somatostatin		A hormone produced in the brain and in the pancreas that helps regulate the body's production and release of many hormones, including growth hormone and insulin.
Somogyi effect		A sudden swing from a low blood glucose level to a high one. The body experiences this shift without external stimulus, but the effect can also be caused by taking too much insulin. This effect was named for Dr. Michael Somogyi, the man who first described it.
Sonogram		See Ultrasound.
Soporific		A substance which induces sleep.
Sorbitol		A sugar alcohol the body uses slowly. It is a sweetener used in diet foods. It is called a nutritive sweetener because it has four calories in every gram, just like table sugar and starch. Sorbitol is also produced by the body; too much sorbitol in cells can cause damage.
Spasm		The involuntary contraction of a muscle or muscles.
Spasmolytic		Decreases spasm of smooth muscle or skeletal (striated) muscle.
Spastic		Characterized by spasms.
Spasticity		Muscle stiffness caused by an increase in contractions of the muscle fibers.
Spastic paralysis		Spasticity involving partial paralysis.
Specimen x-ray		An x-ray of tissue that has been surgically removed (surgical specimen).
SPECT		See Single photon emission computed tomography.
Speculum		Instrument used to examine a passage or cavity such as the ear, nose or vagina.
Speech pathologist	Speech therapist	A specialist who evaluates and treats people with communication and swallowing problems.
Speech therapy		A treatment to help someone overcome a problem communicating verbally.
Sperm		Male reproductive cells produced by the testes and transported in the semen; spermatozoa.
Sperm antibody		An antibody against sperm that can be produced by a woman’s immune system.
Spermatocele		A harmless cyst containing fluid and sperm that occurs in the tube through which sperm travel from the testicles.
Sperm banking		Freezing sperm for future use. This procedure can allow men to father children after loss of fertility.
Sperm count		The amount of normally functioning sperm per some unit of semen; used to determine a man's fertility.
Spermicide		Agents that kill sperm by contact.
Spheksophobia		The fear of wasps.
Sphincter		A circular band of muscle fibers that constricts or closes a passage or opening.
Sphygmomanometer		Device used to measure blood pressure.
Spider nevus		A collection of dilated (widened) capillaries on the skin that creates a patch resembling a spider.
Spike		An inflorescence in which the sessile flowers are arranged in a raceme.
Spilling point		When the blood is holding so much of a substance such as glucose (sugar) that the kidneys allow the excess to spill into the urine.
Spina bifida		A birth defect in the spinal column through which the spinal cord may protrude.
Spina bifida occulta		The least dangerous form of spina bifida, in which bones in the spine fail to close but there is no protrusion of the spinal cord or its fluid cushion out of the body.
Spinal canal		The channel in the spinal column that contains the spinal cord.
Spinal column		The skeletal structure composed of the vertebrae that encloses the spinal cord.
Spinal cord		A cord-like bundle of nerves that extends from the base of the brain to the small of the back.
Spinal fusion		The surgical joining of two or more adjacent vertebrae using bone fragments; used to help severe back pain or prevent damage to the spinal cord.
Spinal injury		Where the spine and sometimes the spinal cord are damaged. Spinal injury may result in muscle weakness and paralysis.
Spinal tap		Another term for a lumbar puncture.
Spine		The column of bones and cartilage running along the midline of the back that surrounds and protects the spinal cord and supports the head.
Spiral fracture		A coiled break in a bone, resembling a corkscrew.
Spirometry		A test of lung condition; a person breathes into a machine called a spirometer that measures the volume of air exhaled.
Spleen		The largest organ in the lymphatic system. Located near the stomach, it has a role in the production, storage and breakdown of blood cells.
Splenectomy		The surgical removal of the spleen.
Splenic		Reffering to the spoleen, the largest endocrine gland.
Splenic sequestration crisis		Occurs when a large portion of the child's blood becomes trapped in the spleen. Early signs include paleness, an enlarged spleen, and pain in the abdomen.
Splenitis		An inflammation of the spleen.
Splint		A device that is used to immobilize a part of the body.
Splinter hemorrhage		A splinter-shaped area of bleeding under a fingernail or toenail.
Split dose		Division of a prescribed daily dose of insulin into two or more injections given over the course of a day. Also may be referred to as multiple injections. Many people who use insulin feel that split doses offer more consistent control over blood glucose (sugar) levels.
Spondylitis		An inflammation of the joints between the bones of the spine.
Spondylolisthesis		The slipping of a vertebra in the spine over the one below it .
Spondylolysis		A disorder in which the lower part of the spine is weakened by an abnormally soft vertebra.
Spontaneous abortion		A miscarriage.
Sporotrichosis		An infection with a fungus acquired through a skin wound; causes an ulcer at the site of infection and small, rounded masses of tissue near it.
Sprain		Injury in which ligaments are damaged or a muscle stretched or torn.
Sprue		A digestive disorder in which nutrients cannot be properly absorbed from food, causing weakness and loss of weight.
Sputum		The fluid produced by the lungs and lower airway and ejected by coughing.
Squamous cell carcinoma		A malignant tumor arising from cells known as squamous epithelium.
Squamous cells		Flat cells that look like fish scales; they make up most of the epidermis, the outer layer of the skin.
Squamous intraepithelial lesion	SIL	A general term for the abnormal growth of squamous cells on the surface of the cervix. The changes in the cells are described as low grade or high grade, depending on how much of the cervix is affected and how abnormal the cells are.
Stable angina		Cardiac pain caused by ischemia with a predictable pattern.
Stage		The extent to which cancer has spread from its original site to other parts of the body.
Staging		The process of categorizing the extent of a malignant disease for the purpose of planning treatment.
Standard treatment		A treatment or other intervention currently being used and considered to be of proved effectiveness on the basis of past studies.
Stapedectomy		The surgical removal of a stapes (a sound-conducting bone in the middle ear) that cannot move to transmit sound; performed to treat hearing loss caused by otosclerosis.
Staphylococci		A common bacteria that cause skin infections and a number of other disorders.
Status asthmaticus		A life-threatening asthma attack requiring immediate treatment.
Status epilepticus		A life-threatening succession of epileptic seizures.
STD		See Sexually transmitted disease.
Stein-Leventhal syndrome		See Polycystic ovary syndrome.
Stem cells		Cells that give rise to the different types of blood cells.
Stenosis		The narrowing or closure of an opening or passageway in the body.
Stenosis, aortic		Narrowing of the valve opening between the left ventricle and the aorta.
Stenosis, mitral		Narrowing of the valve between the left atrium and ventricle.
Stent		A device used to hold tissues in place, such as to support a skin graft.
Stereotactic localization		A technique that employs three-dimensional x-ray to pinpoint a specific target area. It is used in conjunction with needle biopsy of nonpalpable breast abnormalities.
Stereotaxic surgery		Brain surgery done through a small opening in the skull and guided by X-rays or computer-aided imaging techniques.
Stereotaxis		Use of a computer and scanning devices to create three-dimensional pictures. This method can be used to direct a biopsy, external radiation, or the insertion of radiation implants.
Sterile		Unable to father children because of a reduced sperm count.
Sterilization		The process by which all microorganisms are killed, as in sterilization of surgical instruments. Or, the process, usually surgical, of rendering a man or woman incapable of reproduction.
Sternum		The breastbone.
Steroid		Any of numerous organic compounds, including cortisone, estrogen, and testosterone, each of which has many effects on the body.
Steroidal chemicals		Group of chemicals with same properties as steroids. Steroids are fat-soluble compounds with carbon and acid components. They are found in nature in the form of hormones and bile acids, and in plants as naturally occurring drugs, such as digitalis.
Steroids	Roids	A large group of chemical substances classified by chemical structure. Steroids include drugs used to relieve swelling and inflammation (such as prednisone), vitamin D, and sex steroids (such as testosterone).
Stethoscope		Device for listening to sounds produced in the body.
Stiff hand syndrome		Thickening of the skin of the palm that results in loss of ability to hold hand straight. This condition occurs only in people with diabetes.
Stillbirth	Late fetal death	A baby that is born dead after the 28^th week of pregnancy.
Stillborn		Dead at birth.
Stimulant		Stimulates (temporarily arouses or accelerates) physiological activity of an organ or organ system.
Stoma		A surgically formed opening on a body surface.
Stomach		A sac-like organ to which food is delivered by the esophagus.
Stomach bypass		A surgical procedure to treat an obstructed stomach or severe obesity in which the passage of food is diverted around the stomach and directly into the small intestine.
Stomachic		Promotes increased contraction of stomach muscles
Stomach stapling		A procedure in which the stomach is made smaller by partitioning it off using metal staples; used as an extreme treatment of severe obesity.
Stomatitis		Inflammation of the mucous membranes of the mouth. May occur as a complication of chemotherapy or radiation therapy.
Stool		Body waste excreted from the bowel; feces.
Stool test		A test to see whether there is blood in the bowel movement. Also called a fecal occult blood test A test to check for hidden blood in stool. (Fecal refers to stool. Occult means hidden.)
Strabismus		A condition in which the eyes are not aligned correctly, such as cross-eye (one eye points inward) and walleye (one eye points outward).
Straight-leg raising		A simple test performed in a doctor’s office to check for disk prolapse.
Strain		Injury produced by overuse of a muscle.
Strangulated hernia		A hernia in which the protruding organ or tissue loses its blood supply, requiring emergency surgery.
Strawberry nevus		A bright red, raised birthmark that usually disappears without treatment.
Strep throat		Streptococcal infection of the throat .
Streptococcal bacteria		The most common disease-causing bacteria in humans which can be treated with antibiotics. If left untreated, some types of streptococcal bacteria may give rise to more serious diseases.
Streptococci		The bacteria that cause a variety of diseases, including pneumonia and strep throat.
Streptococcus pneumoniae		A bacteria that causes a very serious type of pneumonia in children with sickle cell disease. Twice daily doses of penicillin by mouth, starting at about 2 months of age, can help to prevent this life-threatening infection in children with sickle cell anemia and sickle beta-thalassemia.
Stress fracture		A bone break resulting from repeated pressure on the bone.
Stress test		A heart-function test that involves monitoring during physical exertion.
Stress ulcers		Acute upper GI ulcers that occur following stressful conditions, e.g., surgery, major burns, or critical head trauma.
Stretch marks		Llines on the skin that occur when the inner skin layer is stretched thin and loses its elasticity.
Striae		Streaks or stripes.
Stroke		An injury of the brain due to bleeding or to an interruption of the blood supply.
Stroke volume		The amount of blood pumped by the left ventricle during one heartbeat.
Study arm		Patients in clinical trials are assigned to one part or segment of a study--a study "arm." One arm receives a different treatment from another.
Stupor		A state of reduced consciousness.
Stye		A pus-filled abscess in the follicle of an eyelash; caused by a bacterial infection.
Styptic		An astringent substance which stops or reduces external bleeding.
Subacute		Of intermediate duration; between acute and chronic.
Subcutaneous		Under the skin.
Subglottis		The lowest part of the larynx; the area from just below the vocal cords down to the top of
Submucosa		The layer of connective tissue under a mucous membrane.
Sucrose	Table sugar	A form of sugar that the body must break down into a more simple form before the blood can absorb it and take it to the cells.
Suction lipectomy		See Liposuction.
Sudden infant death syndrome	SIDS	The sudden, unexplained death of an infant while sleeping.
Sudorific		A substance which promotes sweating.
Sugar		A class of carbohydrates that taste sweet. Sugar is a quick and easy fuel for the body to use. Types of sugar are lactose, glucose, fructose, and sucrose.
Sulfonylureas		Drugs taken by mouth to lower the level of glucose in the blood.
Sunblock		A preparation applied to the skin to limit the effects of exposure to the ultraviolet rays of the sun.
Sunscreen		A substance that blocks the effect of the sun's harmful rays. Using lotions that contain sunscreens can reduce the risk of skin cancer, including melanoma.
Superinfection		A second infection that develops during the course of an original infection.
Superior vena cava		Large vein returning blood from your head and arms to your heart.
Supine		Lying on the back.
Supplement		Nutritionally, a substance such as a vitamin pill, fiber solution, or herbal extract that is consumed in addition to food in order to complete or enhance the diet.
Supportive care		Treatment given to prevent, control, or relieve complications and side effects and to improve the patient's comfort and quality of life.
Suppository		Pharmaceutical preparation in a solid form, intended to be inserted into the rectum, vagina or urethra.
Suppuration		The formation of pus.
Supraglottis		The upper part of the larynx, including the epiglottis; the area above the vocal cords.
Surfactant		A substance lining the air sacs in the lungs which enhances expansion of the lungs during inspiration.
Surgery		An operation.
Surgical biopsy		The complete (excisional) or portional (incisional) surgical removal of an abnormal area of tissue, for microscopic examination. See : Excisional biopsy and Incisional biopsy.
Surrogate		A woman who agrees to become pregnant and give her baby to someone else when the child is born.
Suture		The process of joining two surfaces by stitching; or, the surgical stitch itself.
Swan-Ganz catheter		A catheter used to monitor cardiovascular function.
Sweat glands		Tiny structures in the skin that secrete sweat.
Sweat test		A measure of the saltiness of sweat to help diagnose cystic fibrosis.
Swimmer's ear		See Otitis externa.
Swollen glands		Enlarged lymph nodes usually due to an infection or allergic reaction. Common sites where glands can be felt are in the neck, armpit, and groin.
Sycosis barbae		A bacterial infection of the hair follicles in the beard area.
Sympathetic nervous system		The part of the autonomic nervous system that raises blood pressure and heart rate in response to stress.
Symptom		An abnormal function, sensation, or appearance experienced by an individual. A sign of disease.
Synapse		The junction of two nerve cells.
Syndactyly		A condition in which fingers or toes are fused together.
Syncope		Fainting.
Syndrome		A constellation of symptoms that characterize an ailment.
Syndrome X		Term describing a combination of health conditions that place a person at high risk for heart disease.
Synergy		Substances working together harmoniously.
Synovectomy		The surgical removal of the synovial membrane.
Synovial fluid		The fluid found in a joint.
Synovial membrane		The thin membrane that lines the inside of a joint capsule.
Synovitus		An inflammation of the membrane lining a joint capsule as a result of injury or infection or due to a chronic illness such as rheumatoid arthritis; characterized by redness, swelling, stiffness, and pain.
Syphilis		A sexually transmitted disease; initially causes only painless sores on the genitals but can be life-threatening if untreated.
Syringe		An instrument for injecting or withdrawing liquids.
Systemic		Affecting or pertaining to the entire body rather than one of its parts.
Systemic inflammatory response syndrome		A condition characterized by having two of the following four clinical criteria: fever, rapid breathing, increased heart rate, and abnormal white blood cell count.
Systemic lupus erythematosus		A disease of the immune system that causes inflammation of connective tissue in many areas of the body, including the skin, lungs, heart, joints, and kidneys.
Systemic treatment	Systemic therapy	Treatment that reaches and affects cells all over the body.
Systole		The portion of the heart cycle during which the heart muscle is contracting.
Systolic pressure		The highest blood pressure produced by the contraction of the heart. Recorded as the first number in your blood pressure measurement.