Grin or smirk
smirk
Smiling, beaming
Smirk is one alternative.
smile, smirk
The word smirk is a noun meaning sly smile. Synonyms for the word smirk include beam, grin, leer, simper, grimace, grim, sneer, visage, and smug look.
smirk
Conquettish mean fake or phony. Sometimes it can be used as another word for sarcastic. Example: She put on a conquettish smirk.
Josh had a smirk on his face when he got a B+ on his test.
Smirk does not have a suffix. Usually words with only one syllable, don't have a suffix.
perhaps "grimace"
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