necessity

noun

ne·​ces·​si·​ty ni-ˈse-sə-tē 

-ˈse-stē

plural necessities

1

: the quality or state of being necessary

He questioned the necessity for the change.

2

a

: pressure of circumstance

The plane was compelled by necessity to change its course.

b

: physical or moral compulsion

did it, not because he wanted to, but by necessity

c

: impossibility of a contrary order or condition

submitting to the necessity imposed by the physical laws of the universe

3

: the quality or state of being in need

especially : poverty

had come to help them in their necessity

4

a

: something that is necessary : requirement

Many families could not afford the bare necessities of life.

b

: an urgent need or desire

When his father collapsed, an ambulance became a necessity.

Phrases

of necessity

: in such a way that it cannot be otherwise

also : as a necessary consequence

further changes will occur of necessity

Synonyms of necessity

• requirement
• must

Examples of necessity in a Sentence

Sunscreen is an absolute necessity for the beach.

food, clothes, and other basic necessities

Getting plenty of rest is a necessity.

Without a car, living close to work is a necessity.

All we took with us on our hiking trip were the bare necessities.

Recent Examples on the Web

The necessity of an over-the-door hanger cannot be overstated. —Julia Harrison, Architectural Digest, 1 Dec. 2025

Over recent days, donations amounting to 900 million Hong Kong dollars ($115 million) have poured in from businesses and the community, with people also sending food and necessities to a resource center set up by volunteers in the housing complex. —Chris Lau, CNN Money, 1 Dec. 2025

And it was purely racially based and—against all the evidence to the contrary—that this was military necessity. —Philip Elliott, Time, 1 Dec. 2025

That means there are many who work on one side of the river and live on the other, and are now riding the ferry out of necessity. —Madeline Heim, jsonline.com, 1 Dec. 2025

Word History

Etymology

Middle English necessite, from Anglo-French necessité, from Latin necessitat-, necessitas, from necesse

First Known Use

14th century, in the meaning defined at sense 1

Phrases Containing necessity

• born of necessity
• by necessity
• make a virtue of necessity
• make a virtue (out) of necessity
• necessity is the mother of invention
• necessity of life
• out of necessity

Kids Definition

necessity

noun

ne·​ces·​si·​ty ni-ˈses-ət-ē 

-ˈses-tē

plural necessities

1

: conditions that cannot be changed

forced by necessity

2

: the quality or state of being in need : poverty

3

a

: something that is necessary : requirement

the necessities for camping in comfort

b

: an urgent need or desire

call in case of necessity

Legal Definition

necessity

noun

ne·​ces·​si·​ty

plural necessities

1

a

: the presence or pressure of circumstances that justify or compel a certain course of action

especially : a need to respond or react to a dangerous situation by committing a criminal act

b

: an affirmative defense originating in common law that the defendant had to commit a criminal act because of the pressure of a situation that threatened a harm greater than that resulting from the act see also choice of evils defense at defense sense 2a compare duress, undue influence

2

: something that is necessary especially to subsistence

obligated to provide the necessities of food, clothing, and shelter