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Synonyms

traitorous

American  
[trey-ter-uhs] / ˈtreɪ tər əs /

adjective

  1. having the character of a traitor; treacherous; perfidious.

    Synonyms:
    faithless, treasonous, disloyal
  2. characteristic of a traitor.

    Synonyms:
    faithless, treasonous, disloyal
  3. of the nature of treason; treasonable.

    a traitorous act.

    Synonyms:
    faithless, treasonous, disloyal

Other Word Forms

Etymology

Origin of traitorous

1350–1400; Middle English treterous, traytrous < Old French traitreus; see traitor, -ous

Explanation

If you can't be trusted to keep your best friend's terrible secret, she's going to start thinking of you as traitorous, or completely unfaithful and unreliable. A traitor is someone who betrays the trust another person has put in him, and the adjective traitorous describes this tendency. It is traitorous when a double agent sells her country's secrets to another government: and the traitorous person risks spending her life in prison or even being executed. It's also traitorous to tell your parents that your brother broke the kitchen window, if you've sworn to him that you'll keep his secret.

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Vocabulary lists containing traitorous

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.

See Examples For:

It turns out that a centuries-old house—especially one once owned by the traitorous Benedict Arnold—holds a lot of secrets.

From The Wall Street Journal Aug. 13, 2026

The final of the celebrity edition of the show was the UK's most-watched TV event of 2025, with about 15 million people tuning in to see traitorous comic Alan Carr become king of the castle.

From BBC Jan. 26, 2026

Watching Madix's traitorous bestie Raquel Leviss display loyalty for the cameras transformed the viewing experience, driving home the artificiality of reality TV relationships.

From Salon Dec. 2, 2023

Kai A. Ealy offers a puissant portrayal of Oedipus’ traitorous son Polynecies and Jason Huysman, donning a white suit and cruelly manipulative demeanor, makes a vivid impression as Creon.

From Los Angeles Times Sep. 8, 2023

Camels are traitorous: they walk thousands of paces and never seem to tire.

From "The Alchemist" by Paulo Coelho

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