noun
treason
TREE-zuhn/ˈtriːzn/
Betrayal of one's country, especially by helping its enemies.
The official faces a charge of treason for aiding the enemy.

Etymology
Latin traditio meant a handing over or surrender. Handing someone over to enemies supplied the connection to betrayal, which in treason became a breach of allegiance to one's country or government.
In context
Quizling's actions were seen as a betrayal by many Norwegians. After the war ended in 1945, he was arrested and put on trial for high treason and aiding the enemy.
More examples
- The trial centered on allegations of treason.
- He regarded the betrayal as treason.
- The law distinguished treason from ordinary political disagreement.
Forms
treason
treasonous adjective — involving betrayal of one's country
Similar words
- betrayal
- Breaking loyalty or trust generally.
- sedition
- Incitement against authority, legally distinct from treason.