1. graded adjective & adjective If you describe someone as tight-lipped, you mean that they are unwilling to give any information about something. [+ about] ⇒ Military officials are still tight-lipped about when or whether their forces will launch a ground offensive. 2. graded adjective & adjective Someone who is tight-lipped has their lips pressed tightly together, especially because they are angry or disapproving. ⇒ He was sitting at the other end of the table, tight-lipped and angry.
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