Betray | Mean of betray in English Dictionary

/bɪˈtreɪ/

• Verb
• to give information about (a person, group, country, etc.) to an enemy
1. They betrayed their country by selling its secrets to other governments.
2. He was betrayed (to the authorities) by one of his students.
• to hurt (someone who trusts you, such as a friend or relative) by not giving help or by doing something morally wrong
1. She is very loyal and would never betray a friend.
2. He betrayed his wife with another woman. [=he was unfaithful to his wife]
3. She betrayed her own people by supporting the enemy.
4. I felt betrayed. [=I was hurt because someone betrayed me]
5. You've betrayed our trust. [=we trusted you, but you did something very bad and hurt us]
6. I can't believe you lied to me. I feel as if you've betrayed our friendship. [=you've betrayed me; you've treated me in a way that shows you are not really my friend]
• to show (something, such as a feeling or desire) without wanting or trying to
1. Although he would not smile, his eyes betrayed his happiness. [=his eyes showed that he was happy]
2. She coughed, betraying her presence behind the door.
3. The expression on his face betrayed nothing. [=the expression on his face did not show anything about what he was feeling or thinking]

• to reveal (something that should not be revealed)
1. betray a secret
• to do something that does not agree with (your beliefs, principles, etc.)
1. He felt that he would be betraying his principles if he accepted the money.