Pronunciation: (si-non'u-mē),[key] —n., —pl.-miesfor 3, 4. 1. the quality of being synonymous; equivalence in meaning.
2. the study of synonyms.
3. a set, list, or system of synonyms.
4. Biol.a list of the scientific names, with explanatory matter and location of type or types, for a particular taxonomic group.