8
thoughtless(adjective, feature, state, dull, trait)
7
buoyant(adjective, feature, state, happy, relaxed)
7
calm(adjective, feature, state, cool, happy)
7
cold(adjective, calm, cool, relaxed, indifferent)
7
half-hearted(adjective, cold, indifferent, dead, apathy)
7
incurious(adjective, calm, cool, relaxed, cold)
7
perfunctory(adjective, cold, indifferent, dead, apathy)
6
insensible(adjective, cold, indifferent, dead, unsympathetic)
6
lightsome(adjective, feature, state, trait)
6
negligent(adjective, feature, state, calm, cool)
6
offhand(adjective, calm, cool, mild, relaxed)
6
permissive(adjective, feature, state, attitude, mild)
6
sunny(adjective, feature, state, keen, happy)
6
unenthusiastic
6
unmoved(adjective, cold, indifferent, dead, unsympathetic)
5
composed(adjective, calm, cool, mild, relaxed)
5
cursory(adjective, cool, informal, relaxed, easygoing)
5
debonair(adjective, feature, state, trait)
5
distant(adjective, indifferent, unsympathetic, inattentive, uninterested)
5
dull(adjective, lethargic, languid, indolent)
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APASmart Define. (2015). insouciant thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/insouciant/thesaurus/synonyms
ChicagoSmart Define. 2015. "insouciant thesaurus" https://smartdefine.org/insouciant/thesaurus/synonyms (accessed September 29, 2026).
HarvardSmart Define 2015, insouciant thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/insouciant/thesaurus/synonyms>.
MLASmart Define. "insouciant thesaurus" 14 April 2015. Web. 29 September 2026. <https://smartdefine.org/insouciant/thesaurus/synonyms>