110 entries under placid topic. ×

10
easy-going(adjective, feature, state, calm, quiet)
10
even(adjective, adverb, calm, quiet, soft)
10
moderate(adjective, calm, quiet, light, cool)
10
peaceable(adjective, calm, quiet, kind, smooth)
10
steady(adjective, calm, quiet, cool, smooth)
10
temperate(adjective, calm, quiet, light, cool)
10
unexcitable(adjective, calm, quiet, cool, smooth)
9
level-headed(adjective, calm, cool, smooth, steady)
9
phlegmatic(adjective, calm, quiet, cool, relaxed)
8
soft(adjective, calm, quiet, light, kind)
7
stoical(adjective, calm, quiet, cool, gentle)
6
meek(adjective, calm, quiet, kind, smooth)
6
reserved(adjective, calm, close, quiet, cool)
6
unconcerned(adjective, feature, state, calm, quiet)
6
unemotional(adjective, calm, quiet, cool, moderate)
6
unmoved(adjective, calm, quiet, cool, moderate)
5
indifferent(adjective, feature, state, calm, cool)
4
aloof(adjective, calm, quiet, cool, moderate)
4
apathetic(adjective, calm, cool, relaxed, indifferent)
4
cold-blooded(adjective, calm, cool, detached, blank)
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APASmart Define. (2015). serene thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/serene/thesaurus/synonyms
ChicagoSmart Define. 2015. "serene thesaurus" https://smartdefine.org/serene/thesaurus/synonyms (accessed September 29, 2026).
HarvardSmart Define 2015, serene thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/serene/thesaurus/synonyms>.
MLASmart Define. "serene thesaurus" 10 April 2015. Web. 29 September 2026. <https://smartdefine.org/serene/thesaurus/synonyms>