tight-lipped
... black-lipped sea krait 扁尾蛇 closemouthed; tight-lipped 口紧 four lipped cam 四凸耳凸轮 ...
closemouthed
collar edge appears tight ; collar outer edge too tight ; collar outer edge too loose ; collar edge appears loose
lapel edge appears tight ; lapel outer edge too tight ; lapel edge appears loose ; lapel edge seems tight
PORTNUT
口紧,指说话小心谨慎;不随便透露情况或应允别人。如:一个口紧的私人秘书。