betrayal
noun
ADJ. personal | final, ultimate His defection to the other side was the ultimate betrayal.
VERB + BETRAYAL regard sth as, see sth as, view sth as The business community regarded the measures as a betrayal of election promises.
PREP. ~ of a betrayal of his friends The decisions were a betrayal of everything my father stood for.
PHRASES an act of betrayal, a betrayal of (sb's) trust, a feeling/sense of betrayal