°A distortion of the
countenance, whether habitual, from
affectation, or momentary and occasional, to express some feeling, as contempt, disapprobation, complacency, etc.; a
smirk; a made-up face.
"I trundle off to bed, eyes brimming, face twisted into a grateful glistening grimace, and awaken the next day wondering what all the fuss was about." — Opera News, March 2005
verb
°To make grimaces; to distort one's face; to make faces.