SINCE PHYSICIANS are rarely semanticists, many common terms have been endowed with specific medical or scientific connotations through the process of unfortunate selection, extensive use, and periodic redefinition. Such is the case with the terms "habituation" and "addiction" as used by physicians and scientists to denote the excessive use and the abuse of drugs which affect the central nervous system. Unfortunately, no qualitative distinction between the terms is implied in their common use. These terms are usually employed as if they were synonymous. By association, both terms have an almost generic connotation of evil and are used to indicate illicit ecstasy, guilt, and sin. If any distinction is made between the terms by the layman, the term "addiction" usually carries the greater stigma. Thus, great confusion exists in attempting to harmonize medical with common meanings, since the public image of a drug is conditioned by its implications in sociological rather