The Collaborative International Dictionary of English v.0.48:

Selfish \Self"ish\, a.
   1. Caring supremely or unduly for one's self; regarding one's
      own comfort, advantage, etc., in disregard, or at the
      expense, of those of others.
      [1913 Webster]

            They judge of things according to their own private
            appetites and selfish passions.       --Cudworth.
      [1913 Webster]

            In that throng of selfish hearts untrue. --Keble.
      [1913 Webster]

   2. (Ethics) Believing or teaching that the chief motives of
      human action are derived from love of self.
      [1913 Webster]

            Hobbes and the selfish school of philosophers.
                                                  --Fleming.
      [1913 Webster]

WordNet (r) 3.0 (2006):

selfish
    adj 1: concerned chiefly or only with yourself and your
           advantage to the exclusion of others; "Selfish men
           were...trying to make capital for themselves out of the
           sacred cause of civil rights"- Maria Weston Chapman [ant:
           unselfish]

Moby Thesaurus II by Grady Ward, 1.0:

61 Moby Thesaurus words for "selfish":
   acquisitive, ambitious for self, autistic, avaricious, careerist,
   covetous, egocentric, egocentristic, egoistic, egoistical,
   egomaniacal, egotistic, egotistical, grasping, greedy, grudging,
   illiberal, inconsiderate, individualistic, mean, mercenary,
   miserly, narcissan, narcissine, narcissistic, narcistic, narrow,
   niggardly, parsimonious, penny-pinching, penurious, personalistic,
   possessive, privatistic, remote, self-absorbed, self-admiring,
   self-advancing, self-aggrandizing, self-besot, self-centered,
   self-concerned, self-considerative, self-contained, self-devoted,
   self-esteeming, self-indulgent, self-interested, self-jealous,
   self-loving, self-occupied, self-pleasing, self-seeking,
   self-serving, self-sufficient, stingy, thoughtless, tight,
   tight-fisted, uncharitable, ungenerous



The Devil's Dictionary (1881-1906):

SELFISH, adj.  Devoid of consideration for the selfishness of others.