That cannot be avoided; inevitable
Compelled, mandated, obligatory, or required, especially if by legal process or a statute.
Imposed on one by authority, command, or convention
(Biochemistry) Being a substance that is required for normal functioning but cannot be synthesized by the body and therefore must be included in the diet:
Serving to bind:
Of coercion or tending to coerce
The definition of imperative is something that has authority or is absolutely necessary.
Not remissible; unpardonable:
The definition of optional is available, but not required.
(Law) Without legal obligation or consideration:
The definition of requisite is something required or necessary.
The definition of incumbent is laying on top of something.
Find another word for obligatory. In this page you can discover 20 synonyms, antonyms, idiomatic expressions, and related words for obligatory, like: unavoidable, required, necessary, compulsory, obligation, essential, binding, coercive, imperative, irremissible and mandatory.