noun ne·ces·si·ty \ ni-ˈse-sə-tē , -ˈse-stē \
|Updated on: 17 Jul 2018

Definition of necessity

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
  • submittimg 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.
of necessity
: in such a way that it cannot be otherwise; also : as a necessary consequence
  • further changes will occur of necessity

Examples of necessity in a Sentence

  1. Sunscreen is an absolute necessity for the beach.

  2. food, clothes, and other basic necessities

  3. Getting plenty of rest is a necessity.

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

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

Recent Examples of necessity from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'necessity.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of necessity

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

NECESSITY Defined for English Language Learners


Definition of necessity for English Language Learners

  • : something that you must have or do : something that is necessary

  • : the quality of being necessary

NECESSITY Defined for Kids


noun ne·ces·si·ty \ ni-ˈse-sə-tē \

Definition of necessity for Students

plural necessities
1 : the state of things that forces certain actions
  • The necessity of eating forced her to work.
2 : very great need
  • Call us for help in case of necessity.
3 : the state of being in need : poverty
  • I am forced by necessity to beg.
4 : something that is badly needed
  • He bought a few necessities before his trip.

Law Dictionary


noun ne·ces·si·ty

legal Definition of necessity

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 2a — compare duress, undue influence
2 : something that is necessary especially to subsistence
  • obligated to provide the necessities of food, clothing, and shelter

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to grant as a privilege or special favor

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