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Glossaries - S

We've defined thousands of terms related to health care. This page discusses glossary terms with the letter S.

Saliva (suh-LY-vuh)

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

Salmonella (SAH-moh-NEL-uh)

A bacterium that may cause intestinal infection and diarrhea. See also Gastroenteritis.

Sarcoidosis (SAR-koy-DOH-sis)

A condition that causes small, fleshy swellings in the liver, lungs, and spleen.

Saturated fat

A type of fat that comes from animals.

Schatzki's Ring (SHAHTS-keez ring)

Sclerotherapy (SKLAIR-oh-THEH-ruh-pee)

A method of stopping upper GI bleeding. A needle is inserted through an endoscope to bring hardening agents to the place that is bleeding.


To make and give off such as when the beta cells make insulin and then release it into the blood so that the other cells in the body can use it to turn glucose (sugar) into energy.

Secretin (suh-KREE-tin)

A hormone made in the duodenum. Causes the stomach to make pepsin, the liver to make bile, and the pancreas to make a digestive juice.

Segmentation (SEG-men-TAY-shun)

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

Serotonin (ser-oh-TOE-nin)

an agent that acts to constrict blood vessels and also inhibits gastric secretion.

Shigellosis (SHIH-geh-LOH-sis)

Infection with the bacterium Shigella. Usually causes a high fever, acute diarrhea, and dehydration. See also Gastroenteritis.

Short Bowel Syndrome (short BAH-wul sin-drohm)

Problems related to absorbing nutrients after removal of part of the small intestine. Symptoms include diarrhea, weakness, and weight loss. Also called short gut syndrome.

Short waves

These deliver deep heat to relieve pain. (Short waves are not used much currently because of problems in people with pacemakers.

Shwachman's Syndrome (SHWAHK-munz sin-drohm)

A digestive and respiratory disorder of children. Certain digestive enzymes are missing and white blood cells are few. Symptoms may include diarrhea and short stature.

Side effect

Sigmoid Colon (SIG-moyd KOH-lun)

The lower part of the colon that empties into the rectum.

Sigmoidoscopy (SIG-moy-DAW-skuh-pee)

Looking into the sigmoid colon and rectum with a flexible or rigid tube, called a sigmoidoscope.

Sitz Bath (SITS bath)

A special plastic tub. A person sits in a few inches of warm water to help relieve discomfort of hemorrhoids or anal fissures.

Small Bowel Enema (smal BAH-wul EN-uh-muh)

X-rays of the small intestine taken as barium liquid passes through the organ. Also called small bowel follow-through. See also Lower GI Series.

Small Intestine

Organ where most digestion occurs. It measures about 20 feet and includes the duodenum, jejunum, and ileum.

Somatostatin (SOH-muh-toh-STAH-tun)

A hormone in the pancreas. Somatostatin helps tell the body when to make the hormones insulin, glucagon, gastrin, secretin, and renin.

Splanchnic (SPLANK-nik)

pertaining to the internal organ.

Spasms (SPAH-zumz)

Muscle movements such as those in the colon that cause pain, cramps, and diarrhea.

Spastic Colon (SPAH-stik KOH-lun)

Sphincter (SFEENK-tur)

A ring-like band of muscle that opens and closes an opening in the body. An example is the muscle between the esophagus and the stomach known as the lower esophageal sphincter.


The organ that cleans blood and makes white blood cells. White blood cells attack bacteria and other foreign cells.

Splenic Flexure Syndrome (SPLEN-ik FLEK-shur sin-drohm)

A condition that occurs when air or gas collects in the upper parts of the colon. Causes pain in the upper left abdomen. The pain often moves to the left chest and may be confused with heart problems.



A group of rheumatic diseases that affect the spine, such as Reiter's syndrome and ankylosing spondylitis.

Squamous Epithelium (SKWAH-mus eh-pih-THEE-lee-um)

Tissue in an organ such as the esophagus. Consists of layers of flat, scaly cells.

Statistical significance

the probability that an event or difference occurred as the result of the intervention (vaccine) rather than by chance alone. This probability is determined by using statistical tests to evaluate collected data. Guidelines for defining significance are chosen before data collection begins.

Steatorrhea (STEE-ah-toh-REE-uh)

A condition in which the body cannot absorb fat. Causes a buildup of fat in the stool and loose, greasy, and foul bowel movements.

Steatosis (stee-ah-TOH-sis)

Stenosis (steh-NOH-sis)

Narrowing of a duct or canal.

Stoma (STOH-muh)

An opening in the abdomen that is created by an operation (ostomy). Must be covered at all times by a bag that collects stool.

Stomach (STUH-muk)

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

Stomach Ulcer (STUH-muk UL-sur)

An open sore in the lining of the stomach. Also called gastric ulcer.


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

Stress Ulcer (STRES UL-sur).

An upper GI ulcer from physical injury such as surgery, major burns, or critical head injury.

Stricture (STRIK-sher)

The abnormal narrowing of a body opening. Also called stenosis. See also esophageal stricture and pyloric stenosis.


Disease caused by damage to blood vessels in the brain. Depending on the part of the brain affected, a stroke can cause a person to lose the ability to speak or move a part of the body such as an arm or a leg. Usually only one side of the body is affected.

Subcutaneous Injection

Putting a fluid into the tissue under the skin with a needle and syringe.


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.


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.


Pills or capsules that people take to lower the level of glucose (sugar) in the blood.


A set of signs or a series of events occurring together that make up a disease or health problem.

Synovial (sigh-NO-vee-ahl)

relating to the lubricating fluid in joints.

Synovial fluid

Fluid released into movable joints by surrounding membranes. This fluid lubricates the joint and reduces friction.

Synovitis (sin-oh-VIE-tis)

inflammation of the joints; arthritis.


A thin membrane that lines a joint and releases a fluid that allows the joint to move easily.


A word used to describe conditions that affect the entire body. Diabetes is a systemic disease because it involves many parts of the body such as the pancreas, eyes, kidneys, heart, and nerves.

Systemic lupus erythematosus

Lupus is a type of immune system disorder known as an autoimmune disease, which causes the body to harm its own healthy cells and tissues. This leads to inflammation and damage of various body tissues. Lupus can affect many parts of the body, including the joints, skin, kidneys, heart, lungs, blood vessels, and brain.

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