treason

Nouns

(n) a crime that undermines the offender's government high treason, lese majesty,
(n) disloyalty by virtue of subversive behavior subversiveness, traitorousness,
(n) an act of deliberate betrayal betrayal, perfidy, treachery,

Synonyms

high treason lese majesty subversiveness traitorousness betrayal perfidy treachery

Words of close approximity

treasonable treasonably treasonist treasonous