Part of speech:
Necessary to continued existence or effectiveness:
Incapable of being dispensed with
(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:
The definition of requisite is something required or necessary.
Of, being, or serving as a starting point or basis:
Of main importance; principal; chief
Vital to the resolution of a crisis or the determination of an outcome:
Required by fashion; fashionable
Pertaining to the foundation or basis; serving for the foundation. Hence: Essential, as an element, principle, or law; important; original; elementary.
The definition of imperative is something that has authority or is absolutely necessary.
Necessary for completeness; essential
The definition of needful is something that is required.
The definition of obligatory is necessary, required or expected as a result of law or social custom.
Required beforehand, esp. as a necessary condition for something following
That cannot be avoided; inevitable
Essential quality, fact, or thing
Being more than is needed, useful, or wanted; surplus; excessive
The definition of redundant is more than enough or too much of something.
The definition of important is having great significance or consequence.
Being a substance that is required for normal functioning but does not need to be included in the diet because of the body's ability to synthesize it from other nutrients:
Find another word for indispensable. In this page you can discover 28 synonyms, antonyms, idiomatic expressions, and related words for indispensable, like: vital, needed, necessary, sine qua non, essential, requisite, basic, cardinal, crucial, de rigueur and fundamental.