The article deals with the phenomenon of synonymy in the terminology system of gender linguistics. The existence of absolute and relative synonyms is stated, their structural models are presented. It is emphasized that at the present stage of the terminology system development the synonymy plays a positive role, since it allows the search of the most optimal nominations, in particular the specific matching of borrowings, stimulating the creation of its own terminology. Also the terminological variability, which unlike synonymy does not belong to system-forming relations is analyzed