The Collaborative International Dictionary
Synonymist
Synonymist \Syn*on"y*mist\ (s[i^]n*[o^]n"[i^]*m[i^]st), n. [Cf. F. synonymiste.] One who collects or explains synonyms.
Wiktionary
synonymist
n. A person who studies synonyms.
WordNet
synonymist
n. a student of synonyms