To betray means you do something bad to someone who trusts you. It means you show you are not loyal. People often say this when someone helps an enemy.
He betrayed his best friend in the game.
She betrayed her country during the war.
Betray can mean that something shows a secret by accident. For example, someone's face can show how they feel even if they do not want to tell.
His face betrayed his true feelings.
The voice betrayed that she was nervous.
Betray can also mean to let someone down or not keep a promise. It means you do not do what others hope or expect from you.
The team betrayed the fans with poor play.
He betrayed his promise to help me.
Betray here means to show or tell something that breaks the surprise in a story. It is often used when people reveal the ending by mistake.
The story betrayed the ending too soon.
He betrayed the secret in his speech.
To betray can also mean to give important information or locations to an enemy. It means helping the other side by telling or showing secrets.
He betrayed the hiding place to the soldiers.
The spy betrayed secret plans to enemies.
Betray can mean to show something in a wrong or imperfect way. For example, a person or thing might not fully show the real idea or feeling.
The painting betrays the artist's true style.
His words betrayed a lack of confidence.
