IPA: /ˈʌŋk.tʃəs/
KK: /ʌŋkʧuəs/
Having a smooth, greasy texture or an overly flattering manner that may seem insincere.
The salesperson's unctuous compliments made me feel uncomfortable and suspicious.
Unctuous → It is derived from the Latin word "unctuosus" (meaning oily or greasy), which comes from "ungere" (meaning to anoint or smear). The word describes a texture or quality that is oily or smooth, often used to refer to a person who is excessively flattering or ingratiating.
Think of something that is 'oily' or 'greasy' — that's what 'unctuous' means, often describing a smooth or flattering manner.