1. (a.) Expressing a command; mandatory; necessary\; containing positive command; authoritatively or absolutely directive; commanding; authoritative; as, imperative orders.

2. (a.) Not to be avoided or evaded; obligatory; binding; compulsory; as, an imperative duty or order.

3. (a.) Expressive of command, entreaty, advice, or exhortation; as, the imperative mood.

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

absolute absolutist absolutistic acid acute allegiance arbitrary aristocratic arrogant ascendant assigned task authoritarian authoritative authorized autocratic basic behest bidding binding biting bossy bounden duty burden burning business call of duty canon case of need charge choiceless claimed clamant clamorous clothed with authority coactive code command commanding commandment commitment compelling competent compulsatory compulsive compulsory conclusive conditional consequential considerable constraining controlling convention corrosive critical crucial crying cutting de rigueur decisive decretal decretive decretory dedication deference demanded despotic devoir devotion dictate dictated dictating dictation dictatorial dictum dire necessity direct order directive dogmatic dominant domineering driving duly constituted duties and responsibilities duty effective eminent empowered entailed essential ethics ex officio exigence exigency exigent fealty feudal final forceful forcible form formula fundamental general principle golden rule governing great grinding guideline guiding principle gutsy hard-and-fast harsh hegemonic hegemonistic hest high-handed high-pressure high-priority homage immediacy imperativeness imperial imperious important importunate imposed impressive incisive indicative indispensable inevitable influential insistent instant instructive involuntary irresistible irrevocable jussive law leading line of duty lordly loyalty magisterial magistral mandated mandating mandatory masterful matter of necessity maxim mighty mission mitzvah mode momentous monocratic mood moral mordant must necessary necessitous nervous norm obligating obligation obligative obligatory official onus oppressive optative order ordering ordinance ought overbearing overruling penetrating peremptory permissive piercing pivotal place pleasure poignant potent potential powerful preceptive predicament preeminent prerequisite prescript prescriptive pressing pressingness pressure prestigious principium principle prominent puissant punchy ranking regulation repressive required requisite respect restraining rubric rule ruling say-so self-imposed duty senior sensational settled principle severe sinewed sinewy slashing special order standard stern strict striking strong subjunctive substantial superior suppressive supreme telling tenet totalitarian trenchant tyrannical tyrannous ultimate urgency urgent urgent need vigorous vital weighty will without appeal without choice word word of command