Oleaginousness refers to the quality of being oily or greasy, or often used to describe someone who is excessively flattering or insincere. There are several synonyms to describe this word, including slickness, insincere flattery, unctuousness, glibness, fawning, obsequiousness and sycophancy. These terms are used to describe individuals who use excessive flattery or ingratiating behavior to achieve their goals. People displaying oleaginousness may appear slimy, cunning and manipulative in their efforts to please others. The word is often used in negative contexts to describe someone who is unnaturally smooth or overly polished in their interactions.