There is considerable confusion in the literature concerning the terms monomorphic adenoma, basal cell adenoma, and canalicular adenoma. This article traces the history of these terms as applied to the pathology of salivary gland tumors and attempts to clarify their usage. It is recommended (1) that monomorphic adenoma be used, as it was originally intended, as a nosologic grouping for all benign epithelial salivary gland tumors that are not pleomorphic adenomas, (2) that basal cell adenoma be used to identify a specific entity that is one component of the monomorphic adenoma group and exhibits a number of histologic subtypes, and (3) that canalicular adenoma be used to describe another entity, distinct from basal cell adenomas but also belonging to the monomorphic adenoma group.