When something is abused, it is used incorrectly. In addiction terms, drug or alcohol abuse is used to describe ill-use of chemicals and alcohol. When prescription drugs are not taken as indicated or taken without prescription, the behaviour is described as abuse.
Similarly, if alcohol is drunk in excess, far beyond what a “normal” amount is, this behaviour is described as abuse. Substance or alcohol abuse begins when a person drinks or uses enough to cause problems in one or more areas of his or her life.