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Definitions

grimace

[grim-uhs, gri-meys] / ˈgrɪm əs, grɪˈmeɪs /
NOUN
scowling facial expression
Synonyms
STRONGEST
frown scowl smirk sneer
STRONG
face moue mouth mouthing mug smile
WEAK
wry face
Antonyms
WEAK
grin
VERB
make a pained expression
Synonyms
STRONGEST
contort frown scowl smirk sneer
STRONG
deform distort mouth mug
WEAK
make a face make a wry face misshape screw up one's face
Antonyms
STRONGEST
grin smile
STRONG
beautify

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.