trea·​son | \ˈtrē-zᵊn \

Definition of treason 

1 : the offense of attempting by overt acts to overthrow the government of the state to which the offender owes allegiance or to kill or personally injure the sovereign or the sovereign's family

2 : the betrayal of a trust : treachery

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Examples of treason in a Sentence

He is guilty of treason. reading a friend's diary without permission would have to be regarded as the ultimate act of personal treason

Recent Examples on the Web

And even apart from being dangerous to world peace, Claudia and the KGB’s plot to bring down Gorbachev was a kind of treason, a betrayal of the nation. Todd Vanderwerff, Vox, "The Americans seeks a new “START” in a tremendous series finale," 31 May 2018 Drug trafficking is among nine classes of crime, including murder and treason, which still bear the death penalty in Malaysia. James Griffiths, CNN, "Australian grandmother sentenced to death by hanging for drug smuggling," 24 May 2018 Park Chung-hee’s successors, Chun Doo-hwan and Roh Tae-woo, both ex-army generals, spent time in jail for bribery, treason, munity and other charges after leaving office. Time, "Ousted South Korean President Park Geun-Hye Has Been Sentenced to 24 Years in Prison," 6 Apr. 2018 The Lost Indictment of Robert E. Lee By John Reeves Rowman & Littlefield, 249 pages, $27 The vast majority of the victors in the Civil War had no doubt at all that Lee had committed treason. Fergus M. Bordewich, WSJ, "‘The Lost Indictment of Robert E. Lee’ Review: The Cost of Conciliation," 12 July 2018 Supporting roles are thoughtfully rendered, too, such as a Soviet diplomat who is willing to commit treason for the greater good. The Economist, "The death of the archetypal Russian villain," 28 June 2018 The Rosenbergs were convicted in 1951 of conspiracy to commit treason in transmitting atomic secrets to Russia., "June 20, 1953: Rosenbergs executed," 20 June 2018 Similarly, Paige is on her own, having essentially admitted to treason to Stan and now living without identification or a means of obvious survival. Todd Vanderwerff, Vox, "The Americans finale proved there are TV fates worse than death," 2 June 2018 Pound’s lawyer negotiated his restriction to St. Elizabeths in lieu of facing a death penalty trial for treason. Wayne Catan, idahostatesman, "Book delves into intriguing, misunderstood, maddening mind of Idaho-born Ezra Pound," 8 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'treason.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of treason

13th century, in the meaning defined at sense 2

History and Etymology for treason

Middle English tresoun, from Anglo-French traisun, from Latin tradition-, traditio act of handing over, from tradere to hand over, betray — more at traitor

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Statistics for treason

Last Updated

26 Oct 2018

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Time Traveler for treason

The first known use of treason was in the 13th century

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More Definitions for treason



English Language Learners Definition of treason

: the crime of trying to overthrow your country's government or of helping your country's enemies during war


trea·​son | \ˈtrē-zᵊn \

Kids Definition of treason

: the crime of trying or helping to overthrow the government of the criminal's own country or cause its defeat in war


trea·​son | \ˈtrēz-ᵊn \

Legal Definition of treason 

: the offense of attempting to overthrow the government of one's country or of assisting its enemies in war specifically : the act of levying war against the United States or adhering to or giving aid and comfort to its enemies by one who owes it allegiance

Other Words from treason

treasonous \ -​əs \ adjective

History and Etymology for treason

Anglo-French treison crime of violence against a person to whom allegiance is owed, literally, betrayal, from Old French traïson, from traïr to betray, from Latin tradere to hand over, surrender

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