6
inept(adjective, weak, stupid, idle, inadequate)
6
thoughtless(adjective, feature, state, careless, wild)
5
aimless(adjective, value, insignificant, unimportant, irregular)
5
happy-go-lucky(adjective, feature, state, trait, unconcerned)
5
inefficacious(adjective, inferior, inadequate, limited, feeble)
5
shiftless(adjective, careless, thoughtless, purpose, reckless)
5
unreliable(adjective, careless, immoral, thoughtless, reckless)
5
unthinking(adjective, careless, careful, thoughtless, rash)
5
untrustworthy(adjective, careless, immoral, thoughtless, reckless)
4
bootless(adjective, weak, stupid, inferior, idle)
4
incautious(adjective, careless, wild, thoughtless, purpose)
4
negligent(adjective, feature, state, careless, indifferent)
4
nonchalant(adjective, feature, state, indifferent, trait)
4
powerless(adjective, dull, weak, little)
4
unaccountable(adjective, madcap, irresponsive)
4
unconcerned(adjective, feature, state, careless, indifferent)
4
undependable(adjective, careless, immoral, thoughtless, reckless)
4
vain(adjective, weak, value, inferior, insignificant)
3
blithe(adjective, feature, state, indifferent, trait)
3
cool(adjective, feature, state, indifferent, trait)
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APASmart Define. (2015). feckless thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/feckless/thesaurus/synonyms
ChicagoSmart Define. 2015. "feckless thesaurus" https://smartdefine.org/feckless/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2015, feckless thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/feckless/thesaurus/synonyms>.
MLASmart Define. "feckless thesaurus" 10 April 2015. Web. 20 September 2026. <https://smartdefine.org/feckless/thesaurus/synonyms>