adj. slip·per·i·er, slip·per·i·est
1. Causing or tending to cause sliding or slipping: a slippery sidewalk.
2. Tending to slip, as from one's grasp: a slippery bar of soap.
3. Not trustworthy; elusive or tricky: "How extraordinarily slippery a liar the camera is" (James Agee).
[Alteration of obsolete slipper, from Middle English, from Old English slipor; see lei- in the Appendix of Indo-European roots.]
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