83 entries under serene topic. ×

3
easy(adjective, calm, cool, relaxed, still)
3
emotionless(adjective, cool, unfriendly, blank, aloof)
3
inscrutable(adjective, quiet, cool, moderate, gentle)
3
laid-back(adjective, calm, quiet, cool, moderate)
3
passionless(adjective, cool, unfriendly, blank, aloof)
3
relaxed(adjective, calm, quiet, cool, moderate)
3
sensible(adjective, calm, firm, solid, relaxed)
3
serious(adjective, calm, cool, sensible, dark)
3
solemn(adjective, calm, cool, sensible, dark)
3
together(adjective, calm, quiet, relaxed, casual)
2
hardened(adjective, cool, cold, cruel, blank)
2
poker-faced(adjective, calm, cool, detached, blank)
2
self-assured(adjective, calm, solid, relaxed, certain)
2
unfeeling(adjective, calm, cool, relaxed, cold)
1
deliberate(adjective, calm, quiet, cool, relaxed)
1
possessed(adjective, calm, relaxed, tranquil, easygoing)
1
calmed(adjective, calm, relaxed, tranquil, easygoing)
1
clearheaded(adjective, calm, relaxed, tranquil, easygoing)
1
commonsensical(adjective, calm, relaxed, restrained, tranquil)
1
cool as cucumber(expression, adjective, idiom, calm, quiet)
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APASmart Define. (2015). imperturbable thesaurus. Retrieved September 28, 2026, from https://smartdefine.org/imperturbable/thesaurus/synonyms
ChicagoSmart Define. 2015. "imperturbable thesaurus" https://smartdefine.org/imperturbable/thesaurus/synonyms (accessed September 28, 2026).
HarvardSmart Define 2015, imperturbable thesaurus, Smart Define, viewed 28 September, 2026, <https://smartdefine.org/imperturbable/thesaurus/synonyms>.
MLASmart Define. "imperturbable thesaurus" 10 April 2015. Web. 28 September 2026. <https://smartdefine.org/imperturbable/thesaurus/synonyms>