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definitely vs. defiantly

[def-uh-nit-lee] / ˈdɛf ə nɪt li /

adverb

  1. in a clear and definite manner; unambiguously.

  2. unequivocally; positively.

    Synonyms:
    certainly, absolutely

interjection

  1. (used to express complete agreement or strong affirmation).

    Are you starting your diet tomorrow? Definitely!

[dih-fahy-uhnt-lee] / dɪˈfaɪ ənt li /

adverb

  1. with daring or bold resistance to authority.

    In a fearless display, protesters chanted defiantly at police: "Come and shoot us with your tear gas!"