Adjective thoughtless has 4 senses
- thoughtless - showing lack of careful thought; "the debate turned into thoughtless bickering"
Antonyms: thoughtful, bemused, deep in thought, lost, preoccupied, brooding, broody, contemplative, meditative, musing, pensive, pondering, reflective, ruminative, cogitative, considered, reasoned, well thought out, deliberate, deliberative, excogitative
- heedless, thoughtless, unheeding - marked by or paying little heed or attention; "We have always known that heedless self-interest was bad morals; we know now that it is bad economics"--Franklin D. Roosevelt; "heedless of danger"; "heedless of the child's crying"
- thoughtless, uncaring, unthinking - without care or thought for others; "the thoughtless saying of a great princess on being informed that the people had no bread; `Let them eat cake'"
Antonym: considerate (indirect, via inconsiderate)
- careless, thoughtless, regardless - (usually followed by `of') without due thought or consideration; "careless of the consequences"; "the proverbial grasshopper--thoughtless of tomorrow"; "crushing the blooms with regardless tread"
Antonyms: heedful, attentive, thoughtful (indirect, via heedless)
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