<p><strong>Adjective</strong></p><ul><li>Absolutely necessary or required; unavoidable.</li><li>Of the nature of or expressing a command; commanding.</li><li>Grammar: Noting or pertaining to the mood of the verb used in commands, requests, etc.</li></ul><p><strong>Noun</strong></p><ul><li>A command.</li><li>Something that demands attention or action; an unavoidable obligation or requirement; necessity.</li><li>The imperative mood.</li><li>A verb in this mood.</li><li>An obligatory statement, principle, or the like.</li></ul>