The Collaborative International Dictionary of English v.0.48:

Flush \Flush\, a.
   1. Full of vigor; fresh; glowing; bright.
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            With all his crimes broad blown, as flush as May.
                                                  --Shak.
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   2. Affluent; abounding; well furnished or suppled; hence,
      liberal; prodigal.
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            Lord Strut was not very flush in ready. --Arbuthnot.
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   3. (Arch. & Mech.) Unbroken or even in surface; on a level
      with the adjacent surface; forming a continuous surface;
      as, a flush panel; a flush joint.
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   4. (Card Playing) Consisting of cards of one suit.
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   Flush bolt.
      (a) A screw bolt whose head is countersunk, so as to be
          flush with a surface.
      (b) A sliding bolt let into the face or edge of a door, so
          as to be flush therewith.

   Flush deck. (Naut.) See under Deck, n., 1.

   Flush tank, a water tank which can be emptied rapidly for
      flushing drainpipes, etc.
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