To lip-act is to bite one's lips to telegraph a wide range of emotions (sexuality, anger, indecision, etc.) but not make the emotions believable with other cues.
So good to see a movie where the teenage lead doesn't lip-act all the way through it.

Mike must be a simp to believe Jory's lip-acting that she isn't running around on him.
by ssnow March 3, 2008
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