1) as of the colloquial metaphor "a well oiled machine"
2) as an indication of sexual arousal or readiness (chiefly female)
3) as a colloquial term for intoxication
4) as in a sufficient amount of oil or oil like substance has been applied
5) the preferred state or condition of a female wrestler
2) KY? You've got me well oiled already...
3) Six Long Island's later, I was well oiled.
4) Laying out at the cove? Be sure to get well oiled before you go.
5) Bronze Buns Babes are always well oiled!
Meaning heavily drunk.
Less common but the same as pissed.
Haha look, Jack's having a piss on the fruity. Is he well-oiled or what?
I've had a rough day at work, I'ma have to get oiled up.