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 Hickey made three trips back and forth in the treacherous water to save the boaters one by one. Nicholas Williams, New York Daily News, 25 May 2025 Mastering wet roads: Safety tips for heavy rainfall When heavy rain pours, the risk of flooding and treacherous roads rises. Southern California Weather Report, Oc Register, 24 May 2025 Battle at the Ministry is a family-friendly thrill ride that invites guests to attend the trial of the treacherous former Hogwarts Headmistress Dolores Umbridge after the defeat of Voldemort. Mackenzie Schmidt, People.com, 23 May 2025 Hosted by Manu Bennett, the series followed a group of contestants tasked with climbing a treacherous mountain, all while surmounting mental and social challenges. Ethan Shanfeld, Variety, 22 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
  • Both have been neglected for years: Bridges are crumbling, school buildings disintegrating, and trains — once a symbol of German efficiency — are now so unreliable that some lines are banned from neighboring Switzerland’s railways.
    Tom Chivers, semafor.com, 4 June 2025
  • He’s also become notoriously unreliable as a live act, particularly in the Twin Cities.
    Ross Raihala, Twin Cities, 3 June 2025
Adjective
  • Social media users have wielded AI tools to create deepfakes and spread misinformation—but also to fact-check and debunk false claims.
    Andrew R. Chow, Time, 12 June 2025
  • On Wednesday, Dobbins addressed the story about his false claims.
    Jen McCaffrey, New York Times, 12 June 2025

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Cite this Entry

“Treacherous.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/treacherous. Accessed 16 Jun. 2025.

More from Merriam-Webster on treacherous

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