Thus a "smarmy" person is cloying, over-ingratiating, oleaginous ("oily"), close, and over-familiar.
"Who was that man who pretended to know you so well?"
"Oh, Kenneth. Ignore him. He confuses charm with smarm."
To pull a face that is overtly and knowingly smarmy.
'I just smarmed that girl. She wasn't happy.'
A smarm is usually employed when someone has told you something that they believe is interesting. You can show your disdain for this person by smarming them.
"Ahh... I'm feeling all smarmy now."