What does "slippery" mean?

Slippery: Not affording firm ground for confidence; as, a slippery promise. The slippery tops of human state. Cowley.

Additional senses

  1. 2.Not easily held; liable or apt to slip away. The slippery god will try to loose his hold. Dryden.
  2. 3.Liable to slip; not standing firm. Shak.
  3. 4.Unstable; changeable; mutable; uncertain; inconstant; fickle. "The slippery state of kings." Denham.
  4. 5.Uncertain in effect. L'Estrange.
  5. 6.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.

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