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Synonyms

require

American  
[ri-kwahyuhr] / rɪˈkwaɪər /

verb (used with object)

required, requiring
  1. to have need of; need.

    He requires medical care.

  2. to call on authoritatively; order or enjoin to do something.

    to require an agent to account for money spent.

  3. to ask for authoritatively or imperatively; demand.

    Antonyms:
    forgo
  4. to impose need or occasion for; make necessary or indispensable.

    The work required infinite patience.

  5. to call for or exact as obligatory; ordain.

    The law requires annual income-tax returns.

  6. to place under an obligation or necessity.

    The situation requires me to take immediate action.

    Synonyms:
    necessitate, obligate
  7. Chiefly British. to desire; wish to have.

    Will you require tea at four o'clock?


verb (used without object)

required, requiring
  1. to demand; impose obligation.

    to do as the law requires.

require British  
/ rɪˈkwaɪə /

verb

  1. to have need of; depend upon; want

  2. to impose as a necessity; make necessary

    this work requires precision

  3. (also intr) to make formal request (for); insist upon or demand, esp as an obligation

  4. to call upon or oblige (a person) authoritatively; order or command

    to require someone to account for his actions

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What are other ways to say require? To require something is to have a need for it or to ask for it authoritatively. How does require compare to synonyms want, need, and lack? Find out on Thesaurus.com. 

Related Words

See demand.

Other Word Forms

  • nonrequirable adjective
  • prerequire verb (used with object)
  • quasi-required adjective
  • requirable adjective
  • requirer noun
  • unrequired adjective

Etymology

Origin of require

First recorded in 1300–50; Middle English requiren, from Latin requīrere, equivalent to re- re- ( def. ) + -quīrere, combining form of quaerere “to seek, search for”; quest ( def. )

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

At present, matching a background requires manual tuning of water and solvent levels.

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Mitochondria act as the cell's energy generators, and when they do not function properly, tissues that require high energy, such as the brain, are damaged.

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