necessary

Definition of necessary

1needed to be done, achieved, or present; essential:they granted the necessary planning permission it’s not necessary for you to be here

2determined, existing, or happening by natural laws or predestination; inevitable:a necessary consequence
Philosophy (of a concept, statement, etc.) inevitably resulting from the nature of things, so that the contrary is impossible.
Philosophy (of an agent) having no independent volition.

(usually necessaries)

the basic requirements of life, such as food and warmth: not merely luxuries, but also the common necessaries poor people complaining for want of the necessaries of life
(the necessary) informal the action or item needed:see when they need a tactful word of advice and do the necessary
(the necessary) British informal the money needed: a bag containing my wallet: the money, the necessary

Phrases

a necessary evil: something that is undesirable but must be accepted: for many, paying taxes is at best a necessary evil

late Middle English: from Latin necessarius, from necesse 'be needful'

Remember that necessary and the related word necessity are spelled with one c and a double s.

it’s necessary to cut some services.

Definition of necessary in the US English dictionary