12
senseless(adjective, wrong, careless, silly, foolish)
12
undiplomatic(adjective, sharp, rough, rude, careless)
12
unwary(adjective, cold, forget, uncaring, inattentive)
12
witless(adjective, careless, indifferent, silly, foolish)
11
ill-advised(adjective, rude, careless, wild, silly)
11
tactless(adjective, sharp, rough, rude, careless)
10
brainless(adjective, silly, foolish, stupid, unwise)
10
fatuous(adjective, silly, unwise)
10
improvident(adjective, careless, foolish, casual, bold)
10
impulsive(adjective, rude, careless, silly, foolish)
10
inept(adjective, sharp, rough, careless, foolish)
10
madcap(adjective, rude, careless, crazy, impulsive)
10
unconcerned(adjective, feature, state, sharp, rude)
10
unheedful(adjective, careless, cold, forget, rash)
10
unkind(adjective, person, mean, sharp, rough)
10
vacuous(adjective, careless, indifferent, stupid, blank)
9
flighty(adjective, careless, fickle, reckless, erratic)
9
hotheaded(adjective, rude, careless, wild, silly)
9
impolite(adjective, sharp, rough, rude, careless)
9
unconsidered(adjective, foolish, rash, impetuous, irresponsible)
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APASmart Define. (2016). thoughtless thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/thoughtless/thesaurus/synonyms
ChicagoSmart Define. 2016. "thoughtless thesaurus" https://smartdefine.org/thoughtless/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2016, thoughtless thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/thoughtless/thesaurus/synonyms>.
MLASmart Define. "thoughtless thesaurus" 24 March 2016. Web. 22 September 2026. <https://smartdefine.org/thoughtless/thesaurus/synonyms>