2
unsounded(adjective, silent, muffled, voiceless)
2
untalkative
1
am
1
Say nothing(noun, expression, idiom, taciturnity)
1
aloof(reserved, reticent, uncommunicative)
1
anaudic
1
antisocial(aloof, reserved, reticent, uncommunicative)
1
brief
1
brooding(aloof, reserved, reticent, uncommunicative)
1
brusque
1
buttoned up(expression, adjective, quiet, soft, reticent)
1
checked(quiet, soft, still, silent, hushed)
1
chrysanthemum
1
close-tongued
1
closed up(expression, adjective, quiet, soft, still)
1
cold(aloof, reserved, reticent, uncommunicative)
1
concise
1
curbed(quiet, soft, still, silent, hushed)
1
dead
1
dead of night(expression, idiom)
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APASmart Define. (2015). mum thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/mum/thesaurus/synonyms
ChicagoSmart Define. 2015. "mum thesaurus" https://smartdefine.org/mum/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2015, mum thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/mum/thesaurus/synonyms>.
MLASmart Define. "mum thesaurus" 13 April 2015. Web. 23 September 2026. <https://smartdefine.org/mum/thesaurus/synonyms>