1
bashful(quiet, soft, restrained, still, shy)
1
brooding(aloof, reserved, reticent, uncommunicative)
1
cagey(quiet, restrained, mysterious, private, reticent)
1
calm(verb, adjective, quiet, smooth, subdue)
1
cautious(careful, vague, mysterious, wary, ambiguous)
1
checked(quiet, soft, still, silent, hushed)
1
clam up(expression, close, quiet, gag, quieten)
1
clamming up(expression, close, quiet, reticent, gag)
1
closed(adjective, calm, quiet, smooth, tranquil)
1
closed up(verb, expression, adjective, close, quiet)
1
closemouthed(adjective, quiet, soft, still, shy)
1
cold(aloof, reserved, reticent, uncommunicative)
1
could hear a pin drop(expression, adjective, idiom, close, quiet)
1
covert(mysterious, private, reticent, taciturn, uncommunicative)
1
cryptic(mysterious, private, reticent, taciturn, uncommunicative)
1
curbed(quiet, soft, still, silent, hushed)
1
curt(aloof, reserved, reticent, taciturn, uncommunicative)
1
deathlike(adjective, calm, quiet, smooth, tranquil)
1
deathly(adjective, calm, quiet, smooth, tranquil)
1
deathly quiet(expression, adjective, calm, quiet, smooth)
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APASmart Define. (2013). clammed up thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/clammed_up/thesaurus/synonyms
ChicagoSmart Define. 2013. "clammed up thesaurus" https://smartdefine.org/clammed_up/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2013, clammed up thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/clammed_up/thesaurus/synonyms>.
MLASmart Define. "clammed up thesaurus" 18 May 2013. Web. 22 September 2026. <https://smartdefine.org/clammed_up/thesaurus/synonyms>