Imperative /(ĭm*pĕr"ȧ*tĭv)/

Im·per·a·tive

Imperative

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

Imperative

n.
  1. The imperative mood; also, a verb in the imperative mood. (Gram.)