Slippery
Part of speech: adjective
Definition: Of a surface, having low friction, often due to being covered in a non-viscous liquid, and therefore hard to grip, hard to stand on without falling, etc. Evasive; difficult to pin down.
Example sentence: Ideas are elusive, slippery things. Best to keep a pad of paper and a pencil at your bedside, so you can stab them during the night before they get away.
Slimy
Part of speech: adjective
Definition: Of or pertaining to slime; resembling slime; of the nature of slime; viscous; glutinous; also, covered or daubed with slime; yielding, or abounding in, slime.