Source : Webster's Revised Unabridged Dictionary (1913)

Critic \Crit"ic\ (kr?t"?k), n. [L. criticus, Gr. ????, a critic;
   prop., an adj. meaning able to discuss, from ???? to judge,
   discern. See {Certain}, and cf. {Critique}.]
   1. One skilled in judging of the merits of literary or
      artistic works; a connoisseur; an adept; hence, one who
      examines literary or artistic works, etc., and passes
      judgment upon them; a reviewer.

            The opininon of the most skillful critics was, that
            nothing finer [than Goldsmith's ``Traveler''] had
            appeared in verse since the fourth book of the
            ``Dunciad.''                          --Macaulay.

   2. One who passes a rigorous or captious judgment; one who
      censures or finds fault; a harsh examiner or judge; a
      caviler; a carper.

            When an author has many beauties consistent with
            virtue, piety, and truth, let not little critics
            exalt themselves, and shower down their ill nature.
                                                  --I. Watts.

            You know who the critics are? the men who have
            failed in literature and art.         --Beaconsfield.

   3. The art of criticism. [Obs.] --Locke.

   4. An act of criticism; a critique. [Obs.]

            And make each day a critic on the last. --Pope.

Critic \Crit"ic\, a.
   Of or pertaining to critics or criticism; critical. [Obs.]
   ``Critic learning.'' --Pope.

Critic \Crit"ic\, v. i. [Cf. F. critiquer.]
   To criticise; to play the critic. [Obs.]

         Nay, if you begin to critic once, we shall never have
         done.                                    --A. Brewer.

Source : WordNet®

critic
     n 1: a person who is professionally engaged in the analysis and
          interpretation of works of art
     2: anyone who expresses a reasoned judgment of something
     3: someone who frequently finds fault or makes harsh and unfair
        judgments