AbstractThis article deals with legislative definitions. It discusses the purpose and characteristics of legislative definitions which act, inter alia, as a mechanism for creating legal certainty with regard to ambiguous terms, and to prevent cumbrous draftsmanship of legislation. The importance of legislative definitions is that from them, usually, the incidence of law is inferred. Legislative definitions not only determine the legal meaning of a term, rather they coercively determine the sole way by which a term should be used in certain factual circumstances. By that, the law becomes the main source through which language is used as a mechanism for social control. In other words, legislative definitions, contrary to dictionaries' definitions, are authoritative. The article continues to elaborate on the relationship between definitions and the principles of the rule of law and separation of powers, and between definitions and statutory interpretation. Finally, the article focuses on several difficulties...