A person who's betrayed someone has broken their trust or been unfaithful. Betrayal can hurt deeply and damage relationships.
When we say someone's been betrayed, it usually means they felt deceived or hurt by a friend, family member, or partner. This can happen in all kinds of situations – at work, in a romantic relationship, or even just between friends. For example, if you confided in someone about your problems and they went behind your back to talk to the person who's causing them, that would be a betrayal. Sometimes betrayal is intentional, like when someone cheats on their partner, but other times it can be accidental or a result of misunderstandings. The key point is that the trust was broken, and now things are strained between people.
To deliver into the hands of an enemy by treachery or fraud, in violation of trust; to give up treacherously or faithlessly.
Example: an officer betrayed the city
