Толковый словарь английского языка Oxford English Reference - imperative

adj. & n. --adj. 1 urgent. 2 obligatory. 3 commanding, peremptory. 4 Gram. (of a mood) expressing a command (e.g. come here!). --n. 1 Gram. the imperative mood. 2 a command. Derivatives imperatival adj. imperatively adv. imperativeness n. Etymology: LL imperativus f. imperare command (as IN-(2), parare make ready)