unc·tu·ous 
(ŭngkch-əs)
(ŭngkch-əs)adj.
1. Excessively ingratiating or insincerely earnest: was annoyed by the unctuous waiter.
2.
a. Containing or composed of oil or fat.
b. Having the quality or characteristics of oil or ointment; slippery.
3. Abundant in organic materials; soft and rich: unctuous soil.
[Middle English, from Old French unctueus, from Medieval Latin ūnctuōsus, from Latin ūnctum, ointment, from neuter past participle of unguere, to anoint.]
unctu·ous·ly adv.
unctu·ous·ness, unc′tu·osi·ty (-ŏsĭ-tē) n.
Synonyms: unctuous, fulsome, oily, smarmy
These adjectives mean insincerely, self-servingly, or smugly agreeable or earnest: asked a favor in an unctuous tone of voice; gave the dictator a fulsome introduction; oily praise; smarmy self-importance.
These adjectives mean insincerely, self-servingly, or smugly agreeable or earnest: asked a favor in an unctuous tone of voice; gave the dictator a fulsome introduction; oily praise; smarmy self-importance.