This article highlights the contribution of acad. Silviu Berejan to the progress of the modern semasiology. Thus, there are specifically mentioned the identified relations in terms of expression (homolexy, paralexy and heterolexy) and in the terms of content (homosemy, parasemy and heterosemy, the author of the article identifies another type of a relationship – parasemolexy, which occurs simultaneously in terms of expression and in those of content. However, the author especially insists on the contribution of acad. S. Berjan to the study of homosemy (synonymy) and to examining the systemic feature of vocabulary on the basis of an analysis performed on lexical microsystems.