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treason Line breaks: trea|son
Pronunciation: /ˈtriːz(ə)n/

Definition of treason in English:


1 (also high treason) [mass noun] The crime of betraying one’s country, especially by attempting to kill or overthrow the sovereign or government: they were convicted of treason
More example sentences
  • The security laws ban treason, sedition, subversion and the theft of state secrets.
  • Military officials initially told the press that he might face charges of espionage and sedition, even treason.
  • He said that his lawyer advised him to leave Kenya as it was rumoured that he would soon be charged with sedition and treason.
1.1The action of betraying someone or something: doubt is the ultimate treason against faith
More example sentences
  • Our ways of saying ‘I’ and ‘me’ and ‘my’ express our ultimate treasons and devotions.
  • God defend your Church from the treasons of men.
  • African-Americans, it is cynically assumed, will remain loyal to the Democrats regardless of the treasons committed against them.
1.2 (petty treason) historical The crime of murdering someone to whom the murderer owed allegiance, such as a master or husband.
Example sentences
  • A wife who killed her husband did not commit murder - she committed the far worse crime of petty treason.
  • Ms Pritchard, my recollection is that a woman charged with murdering her husband, at one stage of the common law, was charged with petty treason and it was heard by a jury of 24.
  • One newspaper said he looked like a horrid wretch, ‘fit evidently for petty treason.’


Middle English: from Anglo-Norman French treisoun, from Latin traditio(n-) 'handing over', from the verb tradere.

  • tradition from Late Middle English:

    A tradition is something passed on and comes from Latin from tradere ‘deliver’ formed from trans- ‘across’ and dare ‘give’. The abbreviation trad dates from the 1950s, usually in the context of jazz. Traitor (Middle English), someone who hands over things to the enemy, and treason (Middle English) the act of handing over, are from the same root.


Formerly, there were two types of crime to which the term treason was applied: petty treason, the crime of murdering one’s master, and high treason, the crime of betraying one’s country. The crime of petty treason was abolished in 1828 and in modern use high treason is often simply called treason.



Example sentences
  • Outright opposition is treasonous.
  • They had their search radars on, and it was time to light up these treasonous traitors.
  • It is treasonous for Americans and it is disloyal for world leaders.

Words that rhyme with treason

reason, season

Definition of treason in:

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