treason
noun /ˈtriːzn/
  /ˈtriːzn/
 (also high treason)
 [uncountable]- the crime of doing something that could cause danger to your country, such as helping its enemies during a war- an act of high treason against the English crown
- They were charged with treason and sentenced to death.
 Oxford Collocations Dictionaryadjective- high
 - treason against
 - an act of treason
 Word OriginMiddle English: from Anglo-Norman French treisoun, from Latin traditio(n-) ‘handing over’, from the verb tradere.