85 entries under casual topic. ×

10
imprudent(adjective, easy, careless, wild, foolish)
10
incurious(adjective, calm, cool, careless, relaxed)
10
irresponsible(adjective, feature, state, careless, indifferent)
10
slapdash(adjective, careless, indifferent, loose)
10
unheeding(adjective, sharp, rude, careless, cold)
10
unobservant(noun, adjective, careless, cold)
10
unthinking(adjective, sharp, rude, careless, indifferent)
8
loose(adjective, calm, cool, careless, relaxed)
8
oblivious(noun, adjective, soft, careless, indifferent)
7
apathetic(noun, adjective, calm, cool, sharp)
7
easygoing(adjective, feature, state, calm, cool)
7
listless(adjective, calm, cool, sharp, rude)
7
relaxed(adjective, feature, state, calm, cool)
6
aloof(adjective, calm, cool, relaxed, cold)
6
insouciant(adjective, feature, state, calm, cool)
6
offhand(adjective, calm, cool, careless, relaxed)
5
abstracted(noun, adjective, careless, thoughtless)
5
detached(noun, adjective, calm, cool, relaxed)
5
improvident(adjective, careless, bold, thoughtless)
5
incautious(adjective, sharp, rude, careless, indifferent)
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APASmart Define. (2015). negligent thesaurus. Retrieved October 1, 2026, from https://smartdefine.org/negligent/thesaurus/synonyms
ChicagoSmart Define. 2015. "negligent thesaurus" https://smartdefine.org/negligent/thesaurus/synonyms (accessed October 1, 2026).
HarvardSmart Define 2015, negligent thesaurus, Smart Define, viewed 1 October, 2026, <https://smartdefine.org/negligent/thesaurus/synonyms>.
MLASmart Define. "negligent thesaurus" 13 April 2015. Web. 1 October 2026. <https://smartdefine.org/negligent/thesaurus/synonyms>