The Collaborative International Dictionary of English v.0.48:

Dirty \Dirt"y\, a. [Compar. Dirtier; superl. Dirtiest.]
   1. Defiled with dirt; foul; nasty; filthy; not clean or pure;
      serving to defile; as, dirty hands; dirty water; a dirty
      white. --Spenser.
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   2. Sullied; clouded; -- applied to color. --Locke.
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   3. Sordid; base; groveling; as, a dirty fellow.
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            The creature's at his dirty work again. --Pope.
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   4. Sleety; gusty; stormy; as, dirty weather.
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            Storms of wind, clouds of dust, an angry, dirty sea.
                                                  --M. Arnold.

   Syn: Nasty; filthy; foul. See Nasty.
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