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Medical Dictionary - Letter: b

Term	Definition	Pronunciation
b.i.d.	bid twice a day
Ba	barium
BAC	blood alcohol concentration
bacilli	A rod-shaped bacterium.	bah-sil´i
bacillus	A large genus of rod-shaped, gram-positive, spore-bearing bacteria.
back	The rear surface from the shoulders to the hip.
baclofen	A muscle relaxing drug.
bacteremia	The presence of bacteria in the blood. Fever, chills, tachycardia, and tachypnea are common manifestations of bacteremia.
bacteri-	bacteria
bacteria	Single cell living things. One of the three domains of life.	bak-tēr´e-ah
bacterial endocarditis	Inflammation of the heart's lining or valves caused by bacteria in the bloodstream.	bak-tēr'ē-ăl en'dō-kahr-dī'tis
bactericide	A substance that kills bacteria.
bacteriophage	A virus that attacks bacteria.
bacteriuria	The presence of bacteria in the urine. Bacteriuria can be symptomatic or asymptomatic.
BADL	basic activities of daily living
balan/o	glans penis
balanitis	Inflammation of the glans penis.
balanoposthitis	Inflammation of the glans penis in uncircumcised males.
ballism	Abnormal involuntary movements of the limbs.
bandages	Material used for wrapping or binding any part of the body. Used to secure wound dressing or immobilize a limb.
bar/o	pressure, weight
barbiturate	A sedative that depresses respiratory rate, blood pressure, temperature and the central nervous system.
bariatric surgery	Surgical procedures aimed at producing major weight reduction in patients with morbid obesity.
bariatrics	Activities related to weight reduction in patients with obesity including diet, exercise, medication and surgery.	bar″e-at´riks
baroreceptor	One of the blood pressure sensitive nerve ending in heart's atria, aorta and the carotid sinuses.
barotrauma	Injury caused by ambient pressure changes especially to the ear drums and lungs.
barrier cream	Lotions and ointments used to protect the skin from allergens and irritants.
bary-	heavy, hard, dull
bas	basilar
bas/o	base, bottom
basal cell carcinoma	A malignant tumor. A common form of skin cancer. Metastasis is rare.
basal ganglia	Large grey masses at the base of the cerebral hemisphere.
basal metabolism	The minimum amount of energy needed to maintain vital body functions.
basi-	base, foundation
basilar membrane	A basement membrane in the cochlea that supports the hair cells of the organ of Corti.
basophils	Granular leukocytes which stain blue-black with basic dyes. Active in inflammatory responses.
bathy-	depth, deep
battery	1) The wrongful use of force on a person. 2) A electrical energy source formed by two or more electrolytic cells.
bayes theorem	A probability theorem used in clinical decision analysis for estimating the probability of a particular diagnosis given the appearance of some symptoms or test result.
BBB	bundle branch block
BBT	basal body temperature
BCLS	basic cardiac life support
BE	below elbow
bed rest	Confinement of an patient to bed for therapeutic reasons.
behavior	The observable response of a man or animal to a situation.
behaviorism	A psychologic theory, developed by John Broadus Watson, concerned with studying and measuring behaviors that are observable.
Bell's Palsy	Temporary facial paralysis, 7th cranial nerve. Sudden onset. Usually one-side asymmetry.
belly	The central fleshy part of a muscle.
beneficence	The act of being kind, charitable, or beneficial. The ethical principle of beneficence requires that researchers should have the welfare of the research participant as a goal of any clinical trial.
benign	Nonmalignant. A non-cancerous tumor.
benzene	Toxic flammable liquid hydrocarbon byproduct of coal distillation.
benzocaine	A local anesthetic applied topically.
beriberi	A disorder caused by a deficiency of thiamine (vitamin B1) and characterized by heart failure and edema.
beta blocker	Drugs that slow heart rate and reduce pumping force. Used to treat high blood pressure, angina, heart failure, migraines.
betahistine	A histamine analog that serves as a vasodilator. Used to reduce the frequency of attacks of vertigo in Meniere's disease.
betamethasone	A glucocorticoid administered by mouth, injection, inhalation or topically to treat disorders in which corticosteroids are indicated.
bezoar	A mass of swallowed hair, fruit or vegetable fibers, or similar substances found in the alimentary canal.
bi-	double, twice, two
bi/o	life
bias	Systematic deviation of results or inferences from the truth.
bib.	drink
bibli/o	books
biceps	A muscle having two heads. Commonly used to refer to the muscles that extend from the shoulder joint to the elbow.
biconcave	Concave on both sides, as in a lens design.
biconvex	Convex on both sides, particularly in a lens design.
bicuspid	A premolar tooth used for grinding food.
bidet	A bathroom fixture, similar to a toilet bowel, used for cleaning the genital and rectal areas.
bil/i	bile, gall
bilat	bilateral
bile	An emulsifying fluid produced in the liver, stored in the gall bladder and secreted into the duodenum.
biliary	Pertaining to bile, the gall bladder or bile ducts.
bilirubin	The orange-yellow pigment of bile.
binaural	Relating to the use of both ears.
binding sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.
binocular	Relating to the use of both eyes.
bioassay	Laboratory determination of the potency of a drug or other substance by comparing its effects on living organisms with a standard preparation.
biochemistry	The study of the composition, chemical structures, and chemical reactions of living things.
bioethics	A branch of applied ethics that studies the value implications of practices and developments in life sciences, medicine, and health care.
biofeedback	The therapy technique of providing immediate status of one's own body functions such as skin temperature, heartbeat, brain waves) as visual or auditory feedback in order to self-control related conditions.
biohazard	Biological substances that pose a risk to the health of living organisms.
biology	Studies concerned with the origin, structure, development, growth, function, genetics, and reproduction of animals, plants, and microorganisms.
bionics	The science of mechanical and electrical systems that have characteristics of living systems.
biophysics	The study of physical phenomena and physical processes as applied to living things.
biopsy	Removal and pathologic examination of small pieces of tissue from the living body.
biostatistics	The application of statistics to biological systems and organisms involving the retrieval or collection, analysis, reduction, and interpretation of qualitative and quantitative data.
biotechnology	Techniques for applying biological processes to the production of materials for use in medicine, food production and industry.
biotin	A water-soluble, enzyme co-factor present in minute amounts in every living cell. It is abundant in liver, kidney, pancreas, yeast, and milk.
bipolar disorder	A major affective disorder marked by severe mood swings (manic or major depressive episodes) and a tendency to remission and recurrence.
birthmark	A benign skin blemish present at birth.
bisexuality	An individual who is sexually attracted to both sexes.
BK	below the knee
black eye	A contusion around the eye with discoloration and swelling.
blackhead	A plug of fatty material in the outlet of the sebaceous gland in the skin. Comedo.
blackwater fever	A complication of malaria characterized by acute renal failure and the passage of dark red to black urine.
bladder	A hollow, expandable muscular sac that stores urine produced by the kidneys until excretion.
blast-	bud, germ
blastema	A mass of cells that is still growing and differentiating.
blastocyst	The embryonic form that follows the morula in human development.
blastula	An early non-mammalian embryo that follows the morula stage. A blastula resembles a hollow ball with the layer of cells surrounding a fluid-filled cavity.
blenn-	mucus
blephar/o	eyelid
blepharitis	Inflammation of the eyelids.
blepharoplasty	Cosmetic eyelid surgery. Also called eyelid lift.	blef·ə·rə‚plas·dē
blepharospasm	Spasmodic winking caused by the involuntary contraction of an eyelid muscle.
blindness	The inability to see.
blinking	Brief closing and reopening of the eyelids by involuntary or voluntary action.
blister	Visible accumulations of watery fluid within or beneath the epidermis.
blood	The body fluid that circulates in the vascular system. Whole blood in comprised of blood cells suspended in a liquid medium (plasma).
blood banks	Centers for collecting, characterizing and storing human blood.
blood cell	Any of the cells found in blood. This includes erythrocytes (red cells), leukocytes (white cells) and thrombocytes (platelets).
blood clot	A semisolid mass formed by blood coagulation. Thrombus.
blood coagulation	The process of the interaction of blood coagulation factors that results in an insoluble fibrin clot.
blood count	The number of red or white blood cells in a specified volume of blood.
blood glucose	The concentration of glucose in the blood. Also called blood sugar. Measured regularly in diabetes patients.
blood group	Classification of blood based upon antigens on the surface of the red cell. Many blood grouping systems have been developed. The ABO system is one of the most important.
blood plasma	The liquid part of the blood, free of formed elements and particles.
blood pressure	Pressure of the blood on the arteries, veins and chambers of the heart.
blood sugar	The concentration of glucose in the blood. Measured regularly in diabetes patients.
blood transfusion	The administration of whole blood or a blood component into the blood stream.
blood urea nitrogen	A measure of the concentration of urea in the blood
blood vessels	Any of the tubular vessels conveying the blood (arteries, arterioles, capillaries, venules, and veins).
BM	bowel movement
BMD	bone mineral density
BMI	body mass index
BMR	basal metabolic rate
BMT	bone marrow transplant
body mass index	A formula for determining obesity based upon a person's weight and height.
boil	A tender, inflamed area of skin that contains pus.
bol	pill
bolus	A soft mass of chewed food ready to be swallowed.
bonding	The emotional attachment of mother-child or individuals to pets.
bone	A dense, hard connective tissue that forms the framework of the skeleton.
bone density	The amount of mineral per square centimeter of bone. Bone density is an important predictor for osteoporosis.
bone marrow	The soft, spongy tissue filling the cavities of bones. Its primary function is to produce erythrocytes, leukocytes and platelets.
borborygmus	Belching.
borderline	Relating to health status where the patient has some signs and symptoms of an abnormality but insufficient for a definite diagnosis.
botulism	A rare, but potentially fatal form of food poisoning caused by the bacterium Clostridium botulinum.
bougie	A thin, cylindrical instrument, somewhat flexible, inserted into body canals in order to examine or dilate them.
BP	blood pressure
BPd	blood pressure diastolic
BPH	benign prostatic hyperplasia
bpm	beats per minute
BPs	blood pressure systolic
brachi/o	arm
brachial	Relating to the arm.
brachial artery	The continuation of the axillary artery; it branches into the radial and ulnar arteries.
brachy-	short
brachytherapy	Radiotherapy that uses small sources that are placed on or near tumor tissues.
brady-	slow
bradycardia	Cardiac arrhythmias that are characterized by abnormally slow heart rate, usually below 50 beats per minute in adults.	brăd′ĭ-kär′dē-ə
bradykinesia	Abnormally slow body movement.
bradypnea	Slow breathing.
braille	A system of printing for visually impaired people, consisting of raised dots that are read by touch.
brain	A highly developed part of central nervous system that is contained within the cranium. It consists of cerebrum, cerebellum and other structures in the brain stem.
breast	A mammary gland of women.
breast implantation	Surgical insertion of a sac filled with silicone or other material to augment the female form cosmetically.
breastfeeding	Feeding a baby milk from the breast.
breath sounds	Sounds heard over the lungs and airways, usually with a stethoscope.
breathing	The repeating cycle of inhaling and exhaling air into and out of the lungs.
bregma	The juncture of the coronal and sagittal sutures on the top of the cranium.
brom-	bromine, stench
bronch/o	bronchial tube
bronchi	The two large air tubes of the lungs branching from the trachea. Secondary bronchi, called bronchioles, branch from bronchi.
bronchi/o	bronchial tube
bronchiectasis	Persistent abnormal dilatation of the bronchi caused by chronic infection and inflammation.	brong'kē-ek'tă-sis
bronchitis	Inflammation of the large airways often caused by bacterial and viral infections and by cigarette smoke.	brŏng-kī′tĭs
bronchoconstriction	Narrowing of the lumen of the bronchi restricting airway into and out of the lungs.
bronchodilator	Substance that expands the bronchi and bronchioles, increasing airflow to the lungs.	brŏng′kō-dī-lā′tər
bronchopulmonary	Pertaining to the bronchi and lungs.
bronchorrhea	Abnormal discharge of mucus from the bronchi.	brong″ko-re´ah
bronchoscopes	Endoscopes for the visualization of the interior of the bronchi.
bronchoscopy	Visual examination and possibly treatment of the bronchi, throat, larynx and trachea using a fiber optical device.
bronchospasm	Excessive narrowing of the smooth muscles of the bronchi. Can be heard as a wheezing sound.
bruise	A contusion.
bruit	A murmur heard while auscultating the carotid artery.
bruxism	A disorder characterized by grinding and clenching of the teeth.
BSA	body surface area
BSE	breast self-examination
bubonic plague	Caused by the bite of a rat flea that has previously bitten an infected rat.
bucc/o	cheek
buccal	Relating to the mouth or inside of the cheek.
buffer	A chemical system that functions to control the levels of specific ions in solution. When the level of hydrogen ion in solution is controlled the system is called a pH buffer.
-bulia	will
bulimia	Eating an excess amount of food in a short period of time. It is caused by an abnormal craving for food.
Bulimia Nervosa	An eating disorder characterized by binge eating followed by inappropriate purging (e.g. vomiting or using laxatives) to avoid weight gain.	bu-le´me-ah nĕr-vō'să
bulla	A fluid-filled blister with a diameter over 5 mm.	bul´ah
bullying	Aggressive behavior intended to cause harm or distress. The behavior may be physical or verbal. There is typically an imbalance of power, strength, or status between the target and the aggressor.
BUN	blood urea nitrogen
bundle branch block	A type of heart block where the electrical signals to the ventricles are interrupted at the Bundle of HIS, preventing the simultaneous depolarization of the two ventricles.
bundle of his	Cells that conduct electrical impulses from the atrioventricular node to the ventricles.
bunion	An area of thick tissue over the metatarsal phalangeal joint at the base of the great toe.
bupropion	An antidepressant drug used as an aid to smoking cessation.
burn	Tissue injury caused by heat, cold, chemicals, electricity, radiation and ultraviolet light.
burs/o	bursa (fluid sac near joints)
bursitis	Inflammation of a bursa, the fibrous sac that acts as a cushion between moving structures of bones, muscles, tendons or skin.
butter	The fatty part of milk, separated when milk or cream is churned. A soft, solid, yellowish substance.
buttocks	Either of two fleshy protuberances at the lower posterior section of the trunk or hip consisting of gluteal muscles and fat.
butyr-	butter
BW	body weight
BWS	battered woman syndrome
Bx	biopsy