grim·ace (grĭm'ĭs, grĭ-mās') n. A sharp contortion of the face expressive of pain, contempt, or disgust. intr.v.
grim·aced, grim·ac·ing, grim·ac·es To make a sharp contortion of the face.
[French, from Old French grimache, alteration of grimuche, probably from Frankish *grīma, mask.] grim'ac·er n.
1651, from Fr. grimace, from M.Fr. grimache, from O.Fr. grimuche, possibly from Frank. (cf. O.S. grima), from same P.Gmc. root as grim, + pejorative suffix -azo (from L. -aceus).