Source : Webster's Revised Unabridged Dictionary (1913)

Slippery \Slip"per*y\, a. [See {Slipper}, a.]
   1. Having the quality opposite to adhesiveness; allowing or
      causing anything to slip or move smoothly, rapidly, and
      easily upon the surface; smooth; glib; as, oily substances
      render things slippery.

   2. Not affording firm ground for confidence; as, a slippery
      promise.

            The slippery tops of human state.     --Cowley.

   3. Not easily held; liable or apt to slip away.

            The slippery god will try to loose his hold.
                                                  --Dryden.

   4. Liable to slip; not standing firm. --Shak.

   5. Unstable; changeable; mutable; uncertain; inconstant;
      fickle. ``The slippery state of kings.'' --Denham.

   6. Uncertain in effect. --L'Estrange.

   7. Wanton; unchaste; loose in morals. --Shak.

   {Slippery elm}. (Bot.)
      (a) An American tree ({Ulmus fulva}) with a mucilagenous
          and slightly aromatic inner bark which is sometimes
          used medicinally; also, the inner bark itself.
      (b) A malvaceous shrub ({Fremontia Californica}); -- so
          called on the Pacific coast.

Source : WordNet®

slippery elm
     n : North American elm having rough leaves that are red when
         opening; yields a hard wood [syn: {red elm}, {Ulmus rubra}]