The aim of this article is to give a short review of the deminutive formations in medieval Latin. These formations are as important in the medieval language as in ancient and particularly so-called Late Latin. Attention is focused both on morphological peculiarities concerning the derivational rules in medieval Latin and on the semantic function of deminutives, which is analyzed here in the light of communication theory. In this area the article is inspired by the works of the French scholars M. Fruyt (1989) and F. Gaide (1987).