Synonyms for regardless
negligent, careless, unobservant, unheeding, inattentive, reckless, inconsiderate, inadvertent, blind, unfeeling, deaf, neglectful, unmindful, mindless, insensitive, lax, indifferent, listless, uninterested, unconcerned.
Antonyms alert*, attentive, watchful.
In spite of; usually used with of
despite, aside from, distinct from, without regard to, without considering, at all costs, at any cost, leaving aside; see also although, but 1, notwithstanding.
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