From Longman Dictionary of Contemporary Englishunctuousunc‧tu‧ous /ˈʌŋktʃuəs/ adjective formal PRETENDtoo friendly and praising people too much in a way that seems very insincere SYN ingratiating —unctuously adverb —unctuousness noun [uncountable]
Examples from the Corpus
unctuous• Dave is genuinely friendly without being unctuous.• The fat man loudly prattled unctuous apologies.• Beyond that, it promises to provide a weekly primer on dopey and unctuous behavior among upscale hillbillies who dress well.• unctuous food• Rather, it was a way of rejecting unctuous, masochistic denial - which might narrow his perspectives.• More subtly there is the unctuous sadism of money and of social rank.• He seemed anxious to please, but not in an unctuous way.Origin unctuous (1300-1400) Medieval Latin unctuosus, from Latin unctum “ointment”, from unguere; → UNGUENT