no-no
noun/ˈnəʊ nəʊ/
/ˈnəʊ nəʊ/
[singular] (informal)- a thing or a way of behaving that is not acceptable in a particular situation
不可做的事;不可接受的行为 - Earrings for men were once a definite no-no.
男士耳环曾经是绝对的禁忌。
- Earrings for men were once a definite no-no.