Glossary try the best to avoid the use of medical terms that could make it more difficult to understand the information on this website. Still, there are a number of terms that can't be avoided and that are useful to know because they are so often used by the doctors, nurses, and other medical professionals with whom you might speak. The list below includes the terms used on for which we have provided definitions.

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Term Definition

Presence of bacteria in the blood


Plural: Bacteria
Unicellular microscopic organisms, some of which cause disease


1) Substance that has a hydroxyl (OH) ion, tastes bitter, has a pH greater than 7 and, when combined with an acid, forms a salt; example of a base is ammonia
2) One of the building blocks of DNA and RNA


Type of white blood cell (leukocyte), with coarse granules that stain blue when exposed to a basic dye. Basophils normally constitute 1% or less of the total white blood cell count but may increase or decrease in certain diseases.


1. Mild, non-cancerous, and/or not spreading (compare Malignant), as of a disease or growth, esp. a benign tumor.
2. Associated with disease or condition that has mild or minimal consequences for the patient.

Beta Blockers

Beta Blockers

A group of drugs that blocks the effect of adrenaline, slows the heart rate, and decreases the strength of the heart's contractions and thereby lowers blood pressure and relieves symptoms of angina and arrhythmias

Beta Cells

Specialized cells in the pancreas that produce and secrete insulin


Thick, yellow-green-brown fluid made by the liver, stored in the gallbladder, and discharged into the upper part of the digestive tract (duodenum), where it dissolves fats, preparing them for further digestion.


Pertaining to bile or the ducts of the liver and gall blader


A substance produced by the body, often detectable in body fluids such as blood or urine, that indicates a specific process, condition or disease


Removal of a small amount of tissue and/or fluid; the specimen is usually obtained by cutting or by suction through a needle.

Bite cells

Abnormally-shaped red blood cells with one or more semicircular portions removed from the cell margin, appearing as though the cells have had "bite" or "bites." The "bites" result from the removal of hemoglobin with an altered structure (denatured) by special cells (macrophages) in the spleen. G6PD deficiency is a common disorder that leads to the formation of bite cells, which can be seen in a stained blood smear.


Immature or primitive cell; precursor cell


A basal body especially of a flagellated cell.


Also known as: Vesicle

A small raised area of the outer layer of the skin filled with a watery liquid


Also known as: Furuncle

A painful, inflamed area of skin with a defined border, collection of pus and a hard central core usually caused by a bacterial infection of a hair follicle and surrounding tissue

Bone Marrow

Specialized soft tissue found within bone. Red bone marrow, widespread in the bones of children and found in some adult bones (e.g., pelvis, spine, ribs), is essential for the formation of mature red blood cells. Fat-laden yellow bone marrow, more common in adults, is found primarily at the ends of long bones.


In genetics, the particular sites of disruption when chromosomes break (and recombine)

Brittle diabetes

Describes diabetes that is difficult to control, with frequent swings in blood glucose levels between very high and very low

Broad-spectrum Antibiotic Therapy

Treatment with one or more drugs that is effective against a wide variety of bacteria


A condition in which the airways are stretched and/or widened that can be caused by recurrent inflammation or infection of the airways and results in symptoms such as bluish skin, coughing and wheezing, and shortness of breath


The smaller airway passages/branches of the lower respiratory tract


Also known as: Croup

Inflamed bronchioles, the smaller airway passages/branches of the lower respiratory tract


Also known as: Bronchi (plural)

One of the two main branches of the windpipe (trachea) that lead directly to the lungs