acromegaly: A disorder of the pituitary gland that causes enlargement of hands, feet, and facial features. Nonprescription use of human growth hormones can cause this disorder.

alcohol: A colorless liquid found in beer, wine, and liquor that can cause drunkenness in a person who consumes it.

alcoholism: An illness characterized by excessive drinking and dependence on alcohol. Is often fatal.

amphetamines: Stimulants that increase the heart rate and make the user feel alert and energetic. Often referred to as "speed."

anabolic: Having to do with the building up of muscle.

anabolic androgenic steroids (AAS): Man-made forms of the male hormone testosterone. Taken by injection or in pill form, AAS build muscle mass, power, and speed. They can be harmful to the body.

androgenic: Male-producing. An androgenic hormone, for example, causes masculine changes in the body.

"black market": Describing the illegal business of buying or selling goods, such as...