Adjective regardless has 1 sense
- 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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Adverbial regardless has 1 sense
- regardless, irrespective, disregardless, no matter, disregarding - in spite of everything; without regard to drawbacks; "he carried on regardless of the difficulties"
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