Oleaginous (adjective)
Oily, greasy.
Oleaginous (adjective)
Falsely or affectedly earnest; persuasively suave.
“The oleaginous salesman convinced me to buy a more expensive car.”
Unctuous (adjective)
Oily or greasy.
Unctuous (adjective)
Rich, lush, intense, with layers of concentrated, soft, velvety flavor.
Unctuous (adjective)
Profusely polite, especially unpleasantly so and insincerely earnest.
Wiktionary
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