[ tree-zuhn ]
See synonyms for treason on
  1. the offense of acting to overthrow one's government or to harm or kill its sovereign.

  2. a violation of allegiance to one's sovereign or to one's state.

  1. the betrayal of a trust or confidence; breach of faith; treachery.

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Origin of treason

First recorded in 1175–1225; Middle English tre(i)so(u)n, from Anglo-French; Old French traïson, from Latin trāditiōn-, stem of trāditiō “delivery, transfer, betrayal”; see tradition

synonym study For treason

1. Treason, sedition mean disloyalty or treachery to one's country or its government. Treason is any attempt to overthrow the government or impair the well-being of a state to which one owes allegiance; the crime of giving aid or comfort to the enemies of one's government. Sedition is any act, writing, speech, etc., directed unlawfully against state authority, the government, or constitution, or calculated to bring it into contempt or to incite others to hostility, ill will or disaffection; it does not amount to treason and therefore is not a capital offense. 2. See disloyalty.

Other words from treason

  • su·per·trea·son, noun

Words Nearby treason Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use treason in a sentence

British Dictionary definitions for treason


/ (ˈtriːzən) /

  1. violation or betrayal of the allegiance that a person owes his sovereign or his country, esp by attempting to overthrow the government; high treason

  2. any treachery or betrayal

Origin of treason

C13: from Old French traïson, from Latin trāditiō a handing over; see tradition, traditor

Derived forms of treason

  • treasonable or treasonous, adjective
  • treasonableness, noun
  • treasonably, adverb

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012