5
sharp(adjective, rough, careless, bitter, unkind)
5
shiftless(careless, reckless, erratic, negligent, frivolous)
5
thankless(adjective, inconsiderate, unappreciative, ungrateful)
5
unceremonious(adjective, severe, unkind, uncaring, selfish)
5
uncharitable(adjective, mean, nasty, ill, hostile)
5
uncivil(adjective, sharp, rough, rude, careless)
5
unfeeling(adjective, mean, sharp, rough, harsh)
5
unobliging(adjective, cold, forget, uncaring, inattentive)
5
unserious
5
unsolicitous(adjective, cold, forget, uncaring, inattentive)
5
untactful(adjective, sharp, rough, rude, careless)
4
absentminded(adjective, careless, indifferent, apathetic, distracted)
4
airy(adjective, feature, state, trait, casual)
4
asinine(adjective, silly, foolish, stupid, vulgar)
4
bold(adjective, careless, impulsive, rash, aggressive)
4
breakneck(adjective, wild, quick, rash, reckless)
4
callous
4
carefree(adjective, feature, state, condition, careless)
4
clumsy(adjective, sharp, rough, careless, insensitive)
4
confused(adjective, careless, foolish, stupid, unwise)
10 years ago|30k views|share |citing 
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>