Meaning

noun a contorted facial expression

verb contort the face to indicate a certain mental or emotional state

originFrom French grimace, from Middle French grimace, from Old French grimace, grimuche, from grime (“mask”) (with the pejorative suffix -ace, from Latin -āceus), from Frankish *grīma, *grīmō (“mask”), from Proto-Germanic *grīmô (“mask, helmet”). Cognate with Old English grīma (“mask, visor, helmet, spectre, apparition”). More at grime.

Etymology from Wiktionary, CC BY-SA 3.0