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.

Definitions of deter
  1. verb
    turn away from by persuasion
    synonyms: dissuade
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    cause somebody to adopt a certain position, belief, or course of action; twist somebody's arm
    talk out of
    persuade someone not to do something
    type of:
    advise, counsel, rede
    give advice to
  2. verb
    try to prevent; show opposition to
    synonyms: discourage
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    type of:
    disapprove, reject
    deem wrong or inappropriate
Word Family

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