Imperative

a.	1.	Expressive of command; containing positive command; authoritatively or absolutely directive; commanding; authoritative; as, imperative orders. The suit of kings are imperative. - Bp. Hall.
	2.	Not to be avoided or evaded; obligatory; binding; compulsory; as, an imperative duty or order.
	3.	(Gram.) Expressive of commund, entreaty, advice, or exhortation; as, the imperative mood.
n.	1.	(Gram.) The imperative mood; also, a verb in the imperative mood.

Noun	1.	imperative - a mood that expresses an intention to influence the listener's behavior Synonyms: imperative mood, jussive mood
	2.	imperative - some duty that is essential and urgent
Adj.	1.	imperative - requiring attention or action; "as nuclear weapons proliferate, preventing war becomes imperative"; "requests that grew more and more imperative" Antonyms: beseeching - begging
	2.	imperative - relating to verbs in the imperative mood

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