Source : Webster's Revised Unabridged Dictionary (1913)

Oleaginous \O`le*ag`i*nous\, a. [L. oleaginus, oleagineus,
   belonging to the olive, fr. olea olive: cf. F. ol['e]agineux.
   See {Olive}, {Oil}.]
   Having the nature or qualities of oil; oily; unctuous.

Source : WordNet®

oleaginous
     adj 1: unpleasantly and excessively suave or ingratiating in manner
            or speech; "buttery praise"; "gave him a fulsome
            introduction"; "an oily sycophantic press agent";
            "oleaginous hypocrisy"; "smarmy self-importance"; "the
            unctuous Uriah Heep" [syn: {buttery}, {fulsome}, {oily},
             {smarmy}, {unctuous}]
     2: containing an unusual amount of grease or oil; "greasy
        hamburgers"; "oily fried potatoes"; "oleaginous seeds"
        [syn: {greasy}, {oily}, {sebaceous}]