Necessary
Definition of necessary:
part of speech: adjective
Needful: unavoidable: indispensable: not free.
part of speech: noun
part of speech: noun
A requisite- used chiefly in pl.
part of speech: noun
A thing which can not be done without.
part of speech: adjective
That can not be otherwise; not to be done without; essential; indispensable; as, food is necessary to life; not to be avoided.