adj uncertain in effect.
2. slippery ·adj liable to slip; not standing firm.
3. slippery ·adj wanton; unchaste; loose in morals.
4. slippery ·adj not easily held; liable or apt to slip away.
5. slippery ·adj unstable; changeable; mutable; uncertain; inconstant; fickle.
6. slippery ·adj not affording firm ground for confidence; as, a slippery promise.
7. slippery ·adj 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.