Source : Webster's Revised Unabridged Dictionary (1913)

Egoist \E"go*ist\, n. [F. ['e]go["i]ste. See {Egoism}.]
   1. One given overmuch to egoism or thoughts of self.

            I, dullard egoist, taking no special recognition of
            such nobleness.                       --Carlyle.

   2. (Philos.) A believer in egoism.

Source : WordNet®

egoist
     n 1: a conceited and self-centered person [syn: {egotist}, {swellhead}]
     2: a self-centered person with little regard for others [syn: {egocentric}]