GNU Collaborative International Dictionary of English

Found 2 definitions

1.       
   Imperative , a. [L. imperativus, fr. imperare to command; pref. im- in + parare to make ready, prepare: cf. F. impératif. See Perade, and cf. Empire.]
   Expressive of command; containing positive command; authoritatively or absolutely directive; commanding; authoritative; as, imperative orders.
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   The suit of kings are imperative.
   Bp. Hall.
   
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   Not to be avoided or evaded; obligatory; binding; compulsory; as, an imperative duty or order.
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   (Gram.) Expressive of command, entreaty, advice, or exhortation; as, the imperative mood.
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2.       
   Imperative, n. (Gram.) The imperative mood; also, a verb in the imperative mood.
   1913 Webster