The Collaborative International Dictionary of English v.0.48:

Discriminate \Dis*crim"i*nate\, v. i.
   1. To make a difference or distinction; to distinguish
      accurately; as, in judging of evidence, we should be
      careful to discriminate between probability and slight
      presumption.
      [1913 Webster]

   2.
      (a) To treat unequally.
      (b) (Railroads) To impose unequal tariffs for
          substantially the same service.
          [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Discriminate \Dis*crim"i*nate\, a. [L. discriminatus, p. p. of
   discriminare to divide, separate, fr. discrimen division,
   distinction, decision, fr. discernere. See Discern, and cf.
   Criminate.]
   Having the difference marked; distinguished by certain
   tokens. --Bacon.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Discriminate \Dis*crim"i*nate\, v. t. [imp. & p. p.
   Discriminated; p. pr. & vb. n. Discriminating.]
   To set apart as being different; to mark as different; to
   separate from another by discerning differences; to
   distinguish. --Cowper.
   [1913 Webster]

         To discriminate the goats from the sheep. --Barrow.
   [1913 Webster]

WordNet (r) 3.0 (2006):

discriminate
    adj 1: marked by the ability to see or make fine distinctions;
           "discriminate judgments"; "discriminate people" [ant:
           indiscriminate]
    v 1: recognize or perceive the difference [syn: discriminate,
         know apart]
    2: treat differently on the basis of sex or race [syn:
       discriminate, separate, single out]
    3: distinguish; "I could not discriminate the different tastes
       in this complicated dish"

The Devil's Dictionary (1881-1906):

DISCRIMINATE, v.i.  To note the particulars in which one person or
thing is, if possible, more objectionable than another.