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Showing results for treasonous. Search instead for untreasonous.
Synonyms

treasonous

American  
[tree-zuh-nuhs] / ˈtri zə nəs /

adjective

  1. treasonable.


Other Word Forms

Etymology

Origin of treasonous

First recorded in 1585–95; treason + -ous

Explanation

Anything treasonous involves a betrayal, particularly of your country. Your sister might consider it treasonous if you tell your parents she skipped school to go to the beach. When we betray our friends or families, that's personally treasonous. To betray your country is legally treasonous, since it's a punishable crime. It would be treasonous for a CIA agent to hand over U.S. secrets to an enemy spy—and the root of treasonous is the Latin verb tradere, "to hand over or betray."

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Vocabulary lists containing treasonous

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:

Since Soviet scholars were entirely isolated—any contact with foreigners constituted treasonous “kowtowing to the West”—Freidenberg could not have known Arendt’s work, but she arrived at similar conclusions.

From The Wall Street Journal Apr. 24, 2026

At the time of Gill's conviction Reform UK said it was glad justice was served, calling his actions "reprehensible, treasonous and unforgivable".

From BBC Dec. 16, 2025

When the Framers of the Constitution debated inclusion of a pardon power, they were concerned that a president would pardon his co-conspirators in treasonous plots.

From Slate Jan. 22, 2025

Now his daughter, Sara Nodjoumi, has directed and produced a documentary that investigates the disappearance of hundreds of her father’s paintings that were deemed treasonous and aims to locate them.

From New York Times Mar. 4, 2024

"I serve the Starks, not some treasonous squid of—aah."

From "A Clash of Kings" by George R.R. Martin

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