trea·​son | \ ˈtrē-zᵊn How to pronounce treason (audio) \

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 Accusations of treason and socialism are commonplace. Anchorage Daily News, "A day before Capitol attack, pro-Trump crowd stormed meeting, threatened officials in rural California," 11 Jan. 2021 Alfred Dreyfus, convicted of treason, is publicly stripped of his rank. Bryan Robinson, Fox News, "This Day in History: Jan. 5," 5 Jan. 2021 Also on this day: 1894: French army officer Alfred Dreyfus is convicted of treason in a court-martial that triggers worldwide charges of anti-Semitism. Bryan Robinson, Fox News, "This Day in History: Dec. 22," 22 Dec. 2020 After secretly helping Catherine to her bedchamber in the middle of a miscarriage, Edward is arrested for treason. Maureen Lee Lenker,, "The Spanish Princess recap: The tragedy of Edward Stafford, heresy, and other historical observations," 23 Nov. 2020 The call by the protesters for reform of the monarchy has significantly raised the political temperature in Thailand, angering many older conservative Thais for whom any critical discussion of the royal family is tantamount to treason. William Cummings, USA TODAY, "Transit shutdowns fail to deter fourth day of Thai pro-democracy protests in Bangkok," 18 Oct. 2020 Just telling a joke about Hussein was considered tantamount to treason. New York Times, "They Came for My Father Nearly 30 Years Ago. It Still Haunts Me.," 6 Oct. 2020 Iran's leaders have repeatedly blasted the peace accords as tantamount to treason. Zachary Halaschak, Washington Examiner, "'Keep a low profile': US issues security alert for those in Bahrain after Israel deal," 21 Sep. 2020 His actions triggered a deluge of accusations of treason from high-profile Trump supporters on Twitter and from voters who see a Republican establishment closing ranks. Rob Crilly, Washington Examiner, "MAGA world unloads on Mitch McConnell for congratulating President-elect Biden," 16 Dec. 2020

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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Time Traveler for treason

Time Traveler

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

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Statistics for treason

Last Updated

19 Jan 2021

Cite this Entry

“Treason.” Dictionary, Merriam-Webster, Accessed 20 Jan. 2021.

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More Definitions for treason


How to pronounce treason (audio)

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 How to pronounce treason (audio) \

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 How to pronounce treason (audio) \

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 How to pronounce treason (audio) \ 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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