A verb in imperative mood.
The grammatical mood expressing an order (see jussive). In English, the imperative form of a verb is the same as that of the bare infinitive.
An essential action, a must: something which is imperative.
Having semantics that incorporates mutable variables.
Expressing a command; authoritatively or absolutely directive.
Essential; crucial; extremely important.
Of, or relating to the imperative mood.
In various programming languages, a kind of variable that is assigned a specific data type but may or may not hold an actual value.
Something that is not compulsory, especially part of an academic course.
Not compulsory; left to personal choice; elective.