Source : Webster's Revised Unabridged Dictionary (1913)

Socialist \So"cial*ist\, n. [Cf. F. socialiste.]
   One who advocates or practices the doctrines of socialism.

Socialist \So"cial*ist\, Socialistic \So`cial*is"tic\, a.
   Pertaining to, or of the nature of, socialism.

Source : WordNet®

socialist
     adj 1: of or relating to or promoting or practicing socialism;
            "socialist theory"; "socialist realism"; "asocialist
            party" [syn: {socialistic}]
     2: advocating or following the socialist principles;
        "socialistic government" [syn: {socialistic}] [ant: {capitalistic}]

socialist
     n : a political advocate of socialism