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Synonyms

deter

American  
[dih-tur] / dɪˈtɜr /

verb (used with object)

deterred, deterring
  1. to discourage or restrain from acting or proceeding.

    The large dog deterred trespassers.

  2. to prevent; check; arrest.

    timber treated with creosote to deter rot.

  3. to repel.

    Strongly scented marigolds planted among the melons are supposed to deter beetles.


deter British  
/ dɪˈtɜː /

verb

  1. (tr) to discourage (from acting) or prevent (from occurring), usually by instilling fear, doubt, or anxiety

"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

Other Word Forms

  • determent noun
  • deterrability noun
  • deterrable adjective
  • deterrer noun
  • undeterrability noun
  • undeterrable adjective
  • undeterrably adverb
  • undeterring adjective

Etymology

Origin of deter

First recorded in 1570–80; from Latin dēterrēre “to discourage, put off, frighten,” equivalent to dē-, prefix and preposition + terrēre “to frighten, scare”; de-

Explanation

Deter means to discourage, or literally “to frighten away.” Halloween decorations that are too scary might deter trick-or-treaters, and the risk of being expelled deters kids from cheating in school. Deter comes from the Latin de meaning "away" and terrere meaning "frighten." Something that deters isn’t always scary, though: citronella plants deter mosquitoes, and fines deter people from littering. Teddy Roosevelt's foreign policy dictum "speak softly and carry a big stick" was meant to deter other countries from attacking the United States.

Keep Reading on Vocabulary.com

Vocabulary lists containing deter

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.

It first tested shooting down a satellite in 2007, and has since invested in anti-satellite missile systems and an orbital defense system to deter attacks from orbit, along with enhanced space surveillance technologies.

From Salon • Apr. 9, 2026

A risk for Venture Global is that higher prices and fears of further bottlenecks might deter Asian nations, a growth market for exporters, from signing new contracts.

From The Wall Street Journal • Apr. 7, 2026

"But we will not let them deter us, we proudly campaign for Tisza," Menczel said.

From Barron's • Apr. 3, 2026

Financial transactions with Iran, including paying for the passage of Hormuz, are subject to U.S. sanctions that would deter major global shipping companies.

From The Wall Street Journal • Apr. 3, 2026

He found, always, that matter had retained its dubious solidity in his absence; but this did not deter him.

From "The Astonishing Life of Octavian Nothing, Traitor to the Nation, Volume I: The Pox Party" by M.T. Anderson