habituation /həbich′o̅o̅·ā″shən/ [L, habituare, to become used to] , 1. an acquired tolerance gained by repeated exposure to a particular stimulus such as alcohol. 2. a decline and eventual elimination of a conditioned response by repetition of the conditioned stimulus. 3. psychological and emotional dependence on a drug, tobacco, or alcohol that results from the repeated use of the substance but without the addictive, physiological need to increase dosage. Also called negative adaptation. Compare addiction. 4. (in occupational therapy) internal readiness to demonstrate a consistent pattern of behavior guided by habits and roles; this readiness is associated with specific temporal, physical, or social environments.
