Medical terms - Letter A (page 3) | MedicalVocabulary.org

Abuse, sexual child

Child abuse comprises four basic types of mistreatment: child neglect, physical abuse of a child, emotional abuse of a child, and sexual abuse of a child. Sexual abuse is the least frequently reported form of child…
Abuse, steroid

Use of substances containing anabolic steroids to increase muscle mass. Such steroids can have many side effects when misused, including psychiatric problems, liver tumors, reduction in the size of the male genitals and…
Abuse, substance

See: Substance abuse
Abuse, verbal child

Also known as emotional child abuse, this is the third most frequently reported form of child abuse (after child neglect and physical child abuse), accounting 17% of all cases of child abuse. It is likely that emotional…
Abused inhalant

>Solvents > >Industrial or household solvents or solvent-containing products, including paint thinners or removers, degreasers, dry-cleaning fluids, gasoline, and glue >Art or office supply solvents, including…
AC

Abbreviation for a.c. (ante cibum on a prescription); acromioclavicular (shoulder joint); antecubital (crook of elbow)
AC joint

Acromioclavicular joint located between the acromion (a projection of the scapula that forms the point of the shoulder) and the clavicle (the collar bone). This is a gliding type of joint. The ligaments that serve to…
Acanthamoeba

A microscopic organism, an amoeba, found in soil, dust and fresh water (lakes, rivers, hot springs and hot tubs). Acanthamoeba also occur in brackish water and sea water as well as in heating, venting, and air…
Acanthamoeba keratitis

Infection of the cornea by acanthamoeba, a microscopic water-borne ameba. The disease tends to occur in people who wear contact lens. It can accompany a bacterial infection of the eye. Acanthamoeba keratitis can produce…
Acanthosis nigricans

A skin condition characterized by dark thickened velvety patches, especially in the folds of skin in the axilla (armpit), groin and back of the neck. The condition is complex. It can occur with endocrine diseases such…
Acapnia

Less than the normal level of carbon dioxide in the blood. The opposite of hypercapnia. The origin of the word 'acapnia' is curious. It comes from the Greek 'a-' meaning 'without' + 'kapnos' meaning 'smoke' so acapnia…
Acaricide

An agent, usually a chemical, that kills mites. This class of pesticides is large and includes antibiotic acaricides, carbamate acaricides, formamidine acaricides, mite growth regulators, organophosphate acaricides, and…
Acathisia

See: Akathisia
ACC

Adenoid cystic carcinoma
Accelerated phase of leukemia

Refers to chronic myelogenous leukemia (CML) that is progressing. The number of immature, abnormal white blood cells in the bone marrow and blood is higher than in the chronic phase but not as high as in the blast phase
Acceptable daily intake

Estimate of the amount of a substance in food or drinking water, expressed on a body mass basis (usually mg/kg body weight), which can be ingested daily over a lifetime by humans without appreciable health risk. For…
Access

1. In general, a means of approaching something. 2. In health care, the opportunity or right to receive health care. 3. In dialysis, the point on the body where a needle or catheter is inserted to gain entry to the…
Accessibility of services

The ability to get medical care and services when needed
Accessory

Additional, extra, supplementary, subsidiary to the main thing. An accessory digestive organ is an organ that helps with digestion but is not part of the digestive tract. The accessory nerve is so-called because it…
Accessory digestive organ

An organ that helps with digestion but is not part of the digestive tract. The accessory digestive organs are the tongue, salivary glands, pancreas, liver, and gallbladder
Accessory dwelling unit

(ADU) A separate housing arrangement within a single-family home. The ADU is defined by Medicare as a complete living unit and includes a private kitchen and bath
Accessory nerve

The eleventh cranial nerve, which emerges from the skull and receives an additional (accessory) root from the upper part of the spinal cord. It supplies the sternocleidomastoid and trapezius muscles. The…
Accessory neuropathy

Disease of the accessory nerve which is the eleventh cranial nerve. The accessory nerve supplies the sternocleidomastoid and trapezius muscles. The sternocleidomastoid muscle is in the front of the neck and turns the…
Accessory placenta

An extra placenta separate from the main placenta. Also called a succenturiate or supernumerary placenta. The placenta is the organ joining the mother and fetus, the organ that permits the provision of oxygen and…
Acclimatization to altitude

The main cause of altitude sickness is going too high too fast. Given time, the body can adapt to the decrease in oxygen concentration at a specific altitude, process known as acclimatization. To acclimatize, a number…
Accommodation

In medicine, the ability of the eye to change its focus from distant to near objects (and vice versa). This process is achieved by the lens changing its shape. Accommodation is the adjustment of the optics of the eye to…
Accoucheur

French for a male obstetrician, a physician skilled in the art and science of managing pregnancy, labor and the puerperium (the time after delivery)
Accoucheuse

French for a woman who is an obstetrician (a physician skilled in the art and science of managing pregnancy, labor and the time after delivery) or a midwife (today a non-physician trained to assist a woman during…
ACE (angiotensin converting enzyme)

The angiotensins are peptides (substances smaller than proteins) that act as vasoconstricting agents (causing blood vessels to narrow). Narrowing the diameter of the blood vessels sends up the blood pressure. ACE…
ACE inhibitors

ACE inhibitors: A drug that inhibits ACE (angiotensin converting enzyme) which is important to the formation of angiotensin II. Angiotensin II causes arteries in the body to constrict and thereby raises the blood…
ACE2 (angiotensin converting enzyme 2)

An essential regulator of heart function. Also may be involved in the embryonic development of the heart. The ACE2 gene has been mapped to the X chromosome (band Xp22)
ACEI

ACE inhibitor
Acellular

Not made up of cells or divided into cells. Or lacking intact cells as, for example, an acellular vaccine which may contain cellular material but not complete cells
Acellular vaccine

A vaccine that may contain cellular material but does not contain complete cells
Acentric chromosome

A fragment of a chromosome (one of the microscopically visible carriers of the genetic material DNA) that is lacking a centromere (the 'waist' of the chromosome essential for the division and the retention of the…
Aceruloplasminemia

A genetic disorder in which there is absence of the protein ceruloplasmin from blood and accumulation of iron in the pancreas, liver and brain, causing diabetes and progressive neurodegeneration with the tremors and…
Acetabular

Pertaining to the acetabulum, the cup-shaped socket of the hip joint which is a key feature of the pelvis. The head (upper end) of the femur (the thighbone) fits into the acetabulum and articulates with it, forming a…
Acetabular labrum

Acetabular labrum: A ring of fibrocartilage (fibrous cartilage) that runs around the acetabulum (cup) of the hip joint and increases its depth. The head of the femur (the bone in the thigh) fits in the acetabulum. The…
Acetabulum

The cup-shaped socket of the hip joint. In fact, in Latin an 'acetabulum' is cup, a vinegar cup. The acetabulum is a feature of the pelvis. The head (upper end) of the femur (the thighbone) fits into the acetabulum and…
Acetaminophen

Our Acetaminophen Main Article provides a comprehensive look at the who, what, when and how of Acetaminophen Acetaminophen: A pain reliever and fever reducer. Brand name: Tylenol. The exact mechanism of action of…
Acetate

A molecular ion derived from acetic acid. The formula of acetate is CH3COO-
Acetic acid

The acid most commonly associated with vinegar. Acetic acid is a two-carbon carboxylic acid. Its formula is: CH3COOH. It is the most commercially important organic acid and is used in the manufacture of a broad range of…
Acetoacetate

A molecular ion, CH3COCH2COO-, derived from acetoacetic acid
Acetone

In the body, a chemical that is formed when the body uses fat instead of glucose (sugar) for energy. The formation of acetone means that cells lack insulin or cannot effectively use available insulin to burn glucose for…
Acetyl CoA

See: Acetyl coenzyme A
Acetyl coenzyme A

An important metabolic intermediate, derived from various pathways, such as glycolysis, fatty acid oxidation, and degradation of some amino acids. It also represents a key intermediate in lipid biosynthesis. Commonly…
Acetyl phosphate

A molecular ion which plays a role in the synthesis of the four-carbon fatty acid, butyric acid. The formula for acetyl phosphate is: CH3COPO42-
Acetylcholine

A key chemical in neurons (nerve cells) that acts as a neurotransmitter and carries information across the synaptic cleft, the space between two nerve cells. Abbreviated ACh
Acetylcholinesterase

An enzyme that breaks down the neurotransmitter acetylcholine at the synaptic cleft (the space between two nerve cells) so the next nerve impulse can be transmitted across the synaptic gap. Pesticides of the…
Acetylcysteine

An antioxidant drug used to reduce the thickness of mucus and ease its removal. It is also used to reverse the toxicity of high doses of acetaminophen. Acetylcysteine with hydration significantly reduces the risk of…