(imperatives)
1.
If it is imperative that something is done, that thing is extremely important and must be done. (FORMAL)
It was imperative that he act as naturally as possible...
= vital
ADJ: usu v-link ADJ
2.
An imperative is something that is extremely important and must be done. (FORMAL)
The most important political imperative is to limit the number of US casualties.
N-COUNT: usu with supp
3.
In grammar, a clause that is in the imperative, or in the imperative mood, contains the base form of a verb and usually has no subject. Examples are 'Go away' and 'Please be careful'. Clauses of this kind are typically used to tell someone to do something.
N-SING: the N
4.
An imperative is a verb in the base form that is used, usually without a subject, in an imperative clause.
N-COUNT