Our paper deals with the situation of medieval anatomy language in the pre-Vesalian period. It also explains the necessity of terminology reform undertaken by Vesalius in his De humani corporis fabrica. It describes formation principles of the scientific language of anatomy based on pure classical Latin while eliminating Arabic and Greek elements. Emphasis is laid on Vesalius' effort to unify terms as far as their meaning is concerned, to record lexical items and to create a permanent nomenclature in order to eliminate discrepancies in this field of communication. Our paper contains a lot of information on terminology demonstrating Vesalius' language reform and reminding us of his great achievement, for which he is considered a forerunner of anatomy nomenclature codification. (Ref. 5.)