• (a.) Alt. of Synonymical • (n.) The science, or the scientific treatment, of synonymous words.
Syn`o·nym'ic noun [ Confer German synonymik . See Synonymous .] (Gram.) The science, or the scientific treatment, of synonymous words. 
synonymic A reference to a word having the same or nearly the same meaning as another word in the language; such as, 'joyful, elated', and 'glad'.