Unctuous

Part of speech: adjective

Pronunciation: /ˈʌŋ(k)t͡ʃʊəs/

Definitions

1. Excessively flattering or ingratiating in manner, often in a way that seems insincere or oily
2. Marked by a slippery or greasy quality that can be either tactile or metaphorically suggestive of insincere flattery in behavior
3. Characterized by a smooth, suave quality that conveys insincerity through overzealous charm or flattering demeanor

Etymology: The most striking shift is from grease to flattery. Latin "unctum" was a noun for ointment, and by extension a rich, greasy dish at a banquet, from "unguere," "to anoint or smear with oil." Medieval Latin "unctuosus" simply meant greasy or oily, and English borrowed it in the late Middle Ages in that same literal sense, describing things that were slick to the touch. The move to moral meaning came from the picture of a person whose manner is as smooth and slippery as an oiled surface. Someone who lays on flattery thickly seems to be applying a coat of grease, so the physical quality carried over to speech and behaviour. The word's current sense, insincerely and excessively flattering, grew out of that image of smoothness that conceals something. The same root survives in the relatives found across Europe, such as Italian "untuoso," French "onctueux," and Spanish "untuoso," which mostly keep the sense of oily or creamy texture. English is unusual in having kept the greasy sense in the background while the flattering sense took over the foreground.

Synonyms: insincere, oily, slimy, obsequious, sycophantic

Antonyms: genuine, honest, blunt, frank, unpretentious