1. Excessively ingratiating or insincerely earnest: was annoyed by the unctuous waiter.
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·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.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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