The Collaborative International Dictionary of English v.0.48:

Pretty \Pret"ty\, a. [Compar. Prettier; superl. Prettiest.]
   [OE. prati, AS. pr[ae]ttig, pr[ae]tig, crafty, sly, akin to
   pr[ae]t, pr[ae]tt, deceit, trickery, Icel. prettugr tricky,
   prettr a trick; probably fr. Latin, perhaps through Celtic;
   cf. W. praith act, deed, practice, LL. practica execution,
   practice, plot. See Practice.]
   1. Pleasing by delicacy or grace; attracting, but not
      striking or impressing; of a pleasing and attractive form
      a color; having slight or diminutive beauty; neat or
      elegant without elevation or grandeur; pleasingly, but not
      grandly, conceived or expressed; as, a pretty face; a
      pretty flower; a pretty poem.
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            This is the prettiest lowborn lass that ever
            Ran on the greensward.                --Shak.
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   2. Moderately large; considerable; as, he had saved a pretty
      fortune. "Wavering a pretty while." --Evelyn.
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   3. Affectedly nice; foppish; -- used in an ill sense.
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            The pretty gentleman is the most complaisant in the
            world.                                --Spectator.
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   4. Mean; despicable; contemptible; -- used ironically; as, a
      pretty trick; a pretty fellow.
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   5. Stout; strong and brave; intrepid; valiant. [Scot.]
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            [He] observed they were pretty men, meaning not
            handsome.                             --Sir W.
                                                  Scott.
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   Syn: Elegant; neat; fine. See Handsome.
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