adjective
unctuous
UNGK-choo-us/ˈʌŋktʃuəs/
Oily or greasy in texture.
The unctuous sauce coats the spoon with an oily sheen.

Etymology
From anointing came the literal meaning “greasy,” whose oily image perhaps helped suggest an excessively smooth manner. The source also attributes the figurative sense partly to sarcastic use of unction meaning “deep spiritual feeling.”
In context
The man with the mellifluous voice, the unctuous voice, the man of cryptocurrency and billionaires, Mr. snake oil salesman himself, Mr. Farage.
More examples
- The ointment leaves an unctuous film on my skin.
- Rendered duck fat gives the potatoes an unctuous coating.
- She wipes the unctuous residue from the baking pan.
Forms
unctuous
Similar words
- oily
- Oily emphasizes the presence or feel of liquid oil.
- greasy
- Greasy often suggests an unpleasant coating of fat or grease.