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noun, ne·ces·si·ty \ni-ˈse-sə-tē, -ˈses-tē\

Simple Definition of necessity

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

  • : the quality of being necessary

Source: Merriam-Webster's Learner's Dictionary

Full Definition of necessity

plural necessities

  1. 1 :  the quality or state of being necessary

  2. 2 a :  pressure of circumstance b :  physical or moral compulsion c :  impossibility of a contrary order or condition

  3. 3 :  the quality or state of being in need; especially :  poverty

  4. 4 a :  something that is necessary :  requirement b :  an urgent need or desire

of necessity
  1. :  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.

Origin of necessity

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

First Known Use: 14th century

NECESSITY Defined for Kids


noun ne·ces·si·ty \ni-ˈse-sə-tē\

Definition of necessity for Students

plural necessities

  1. 1 :  the state of things that forces certain actions <The necessity of eating forced her to work.>

  2. 2 :  very great need <Call us for help in case of necessity.>

  3. 3 :  the state of being in need :  poverty <I am forced by necessity to beg.>

  4. 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. 1a :  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. 2 :  something that is necessary especially to subsistence <obligated to provide the necessities of food, clothing, and shelter>

Seen and Heard

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to dishevel or rumple

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