deceive, misguide, misinform, lead astray, delude, fool, misdirect, dupe, hoodwink, betray, lie to
deceive - double-cross - backstab - sell out - rat on - turn on - be disloyal to - break faith with - stab in the back - cross - cheat - trick
To betray means to be disloyal to someone or something that trusts or depends on you. It often involves breaking confidence, revealing secrets, or acting in a way that harms a person, group, or ideal you were expected to support. Betrayal can be emotional, such as cheating in a romantic relationship, or practical, like giving confidential information to an enemy. The word also describes unintentionally revealing something, for example when your expression betrays your true feelings. Overall, it carries a strong sense of broken trust, disappointment, and moral failure.