tight-lipped /ˌtaɪt ˈlɪpt◂/ BrE AmE adjective
1 . unwilling to talk about something:
Diplomats are remaining tight-lipped about the negotiations.
2 . with your lips tightly pressed together because you are angry
tight-lipped /ˌtaɪt ˈlɪpt◂/ BrE AmE adjective
1 . unwilling to talk about something:
Diplomats are remaining tight-lipped about the negotiations.
2 . with your lips tightly pressed together because you are angry
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012