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irregardless vs. regardless

irregardless vs. regardless: What’s the difference?

Regardless means without regard to or in spite of some specific circumstances (usually those that have just been or are about to be mentioned). Irregardless (yes, it’s a word) is a variant of regardless that’s typically used to mean the exact same thing. It’s got an extra negative element, the prefix ir-, so it’s often considered nonstandard.

[ir-i-gahrd-lis] / ˌɪr ɪˈgɑrd lɪs /

adverb

Nonstandard.
  1. regardless.

[ri-gahrd-lis] / rɪˈgɑrd lɪs /

adjective

  1. having or showing no regard; heedless; unmindful (often followed byof ).

    Synonyms:
    careless , neglectful , negligent , inattentive , inattentive
    Antonyms:
    mindful , attentive

adverb

  1. without concern as to advice, warning, hardship, etc.; anyway.

    I must make the decision regardless.

idioms

  1. regardless of,  in spite of; without regard for.

    They'll do it regardless of the cost.