Answer: unctuous

AnswerCrossword Clue
UNCTUOUSSickeningly suave
unctuousmarked by a false or smug earnestness or agreeableness.
unctuous(chiefly of minerals) Having a greasy or soapy feel
unctuousgreasy (containing or resembling grease)
unctuous(of a person) Excessively or ingratiatingly flattering; oily