be tight-lipped
1. Literally, to have one's lips pressed together, as in anger. I knew my girlfriend was angry as soon as I saw that she was tight-lipped and glaring at me. Both of my parents were tight-lipped as they read my failing report card, and I watched them, wishing I could vanish into thin air. Though she'd said we would talk about my punishment later, Mom was tight-lipped all the way home.
2. To be unwilling to talk openly or share details about someone or something. I still don't know anything about Maria's new boyfriend because she's so tight-lipped about him. Don't worry, we can trust my sister to be tight-lipped—she won't tell anyone about our engagement until we do. Does anyone know when we're moving to the new office? Management has been so tight-lipped about everything.
Farlex Dictionary of Idioms. © 2024 Farlex, Inc, all rights reserved.