tight-lipped /ˈtaɪtˈlɪpt/ adjective Learner's definition of TIGHT-LIPPED
[more tight-lipped; most tight-lipped]
1
: not willing to speak about something守口如瓶的 2
: having your lips pressed tightly together because you are thinking hard, angry, etc.(因认真思考或生气)双唇紧闭的