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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.

Facebook and TikTok users labeled Tran, now 25, as traitorous, anti-Vietnam — and Cali.

From Los Angeles Times • Jun. 8, 2025

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

A common plotline, Mr. Zwetsloot says, is imperialist Japanese returning to Korea to assist Americans by reactivating traitorous spy nets.

From Washington Times • Jul. 26, 2023

FBI director Louis Freeh called Hanssen's betrayal "the most traitorous actions imaginable against a country governed by the rule of law".

From BBC • Jun. 6, 2023

Wait, did she just use me to justify her traitorous actions?

From "I'll Give You the Sun" by Jandy Nelson