Synonym Chooser

How is the word treacherous different from other adjectives like it?

Some common synonyms of treacherous are disloyal, faithless, false, perfidious, and traitorous. While all these words mean "untrue to what should command one's fidelity or allegiance," treacherous implies readiness to betray trust or confidence.

a treacherous adviser

When can disloyal be used instead of treacherous?

Although the words disloyal and treacherous have much in common, disloyal implies a lack of complete faithfulness to a friend, cause, leader, or country.

disloyal to their country

When could faithless be used to replace treacherous?

While in some cases nearly identical to treacherous, faithless applies to any failure to keep a promise or pledge or any breach of allegiance or loyalty.

faithless allies

Where would false be a reasonable alternative to treacherous?

The words false and treacherous are synonyms, but do differ in nuance. Specifically, false stresses the fact of failing to be true in any manner ranging from fickleness to cold treachery.

betrayed by false friends

How do perfidious and faithless relate to one another, in the sense of treacherous?

Perfidious adds to faithless the implication of an incapacity for fidelity or reliability.

a perfidious double-crosser

When is traitorous a more appropriate choice than treacherous?

The synonyms traitorous and treacherous are sometimes interchangeable, but traitorous implies either actual treason or a serious betrayal of trust.

traitorous acts punishable by death

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of treacherous Watt Avenue is especially treacherous for pedestrians: Data from UC Berkeley’s Transportation Injury Mapping System shows in a decade through 2023, more than 80 drivers struck pedestrians on Watt and severely injured or killed them. Ariane Lange, Sacbee.com, 8 May 2025 It was depicted as being full of the country's worst criminals, offering harsh conditions and virtually no hope of escape, surrounded by cold and treacherous waters. Bill Chappell, NPR, 5 May 2025 The most treacherous segment, including a perilous crossing over the drifting ice of Norton Sound, fell to Leonhard Seppala and his lead dog, Togo. Scott Travers, Forbes.com, 6 Apr. 2025 For Tesla and other American manufacturers, the path forward is treacherous. Jackie Snow, Quartz, 28 Apr. 2025 See All Example Sentences for treacherous
Recent Examples of Synonyms for treacherous
Adjective
  • Michael Fassbender plays a British intelligence officer tasked with finding who leaked a top-secret software program and betrayed their country, and the list of five potentially traitorous suspects includes his own high-profile wife (Cate Blanchett).
    Brian Truitt, USA Today, 10 May 2025
  • Smith made out their former collaborators to be ungrateful and traitorous, and the kids weren't given the space to question her command.
    Zoey Lyttle, People.com, 18 Apr. 2025
Adjective
  • The cooling system in her second-story apartment in Albuquerque, New Mexico, had always been unreliable.
    Ignacio Calderon, USA Today, 21 May 2025
  • This showed that changes in the truck's speed produced turbulence in the liquid helium, making measurements of its presence unreliable.
    John Timmer, ArsTechnica, 19 May 2025
Adjective
  • Big banks are not allowed to cheat their customers with false advertising and misleading promises.
    Suzanne Blake, MSNBC Newsweek, 19 May 2025
  • The temperature of online discourse can often provide a false reading of a fanbase’s opinion on a manager or a team.
    Jordan Campbell, New York Times, 19 May 2025

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Cite this Entry

“Treacherous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/treacherous. Accessed 27 May. 2025.

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