/ ˈɔɪli; NAmE / adjective ( oil·ier , oili·est )
1.
containing or covered with oil :
oily fish
an oily rag
2.
feeling, tasting, smelling or looking like oil :
an oily substance
3.
( disapproving ) ( of a person or their behaviour ) trying to be too polite, in a way that is annoying :
an oily smile
SYN obsequious
► oili·ness noun [ U ]