You "bite your tongue" to keep yourself quiet and not say what you want to say. Example: "I wanted to tell her what I really thought of her dress, but I just bit my tongue." It is not always right to speak out and express what comes to mind; at times you should bite your tongue and keep quiet. Example: "Whenever that professor says something I don't like, I have to bite my tongue." When you really want to speak out, but you know you should not, it is best to just bite your tongue. Example: "Just as the coach started yelling, he slipped and fell. We all had to bite our tongues to keep from laughing."