1[uncountableU]BETRAYbehaviour in which someone is not loyal to a person who trusts them, especially when this behaviour helps that person’s enemies 背信弃义,不忠,背叛
the treachery of those who plotted against the king
密谋反对国王者的不忠行为
2.[countableC usually plural]BETRAY a disloyal action against someone who trusts you 背叛行为;欺骗行为