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Indispensable
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Indispensible
The word imperative is an adjective. It is another word for essential.
Judy, Judy, Judy...
Oh shut up.
Yes, the noun 'necessity' is an abstract noun, a word for something deemed indispensable; a word for a concept.
A total of eight languages are available in this indispensable travel companion.
vital, necessary, crucial, needful, essential, basic, key, fundamental
Indispensable was created on 2010-09-21.
Evidence is indispensable to solve the crime scene.