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Synonyms

traitor

American  
[trey-ter] / ˈtreɪ tər /

noun

  1. a person who betrays another person, a cause, or any trust.

  2. a person who commits treason by betraying their country.


traitor British  
/ ˈtreɪtə /

noun

  1. a person who is guilty of treason or treachery, in betraying friends, country, a cause or trust, etc

"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

Etymology

Origin of traitor

First recorded in 1175–1225; Middle English from Old French from Latin trāditōr-, stem of trāditor “betrayer”; see traditor

Explanation

A traitor says one thing but does another. If you promise a friend you'll keep his secret, but instead you blab it to everyone, you're a traitor. The word origin says it all: traditorem is the Latin word for "betrayer." Liar? Yes. Backstabber? Yes. True friend? Heavens, no. Traitors betray the trust of those who have faith in them or believe their promises. Traitor also applies to a person who betrays his country by committing treason: turning against his own government, perhaps by selling secret information.

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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.

"Before I won, you had people shouting out 'you big traitor'," she said.

From BBC • Feb. 26, 2026