off colour

Từ điển Oxford Advanced Learner 8th

ˌoff ˈcolour 7 [off colour] BrE NAmE (especially US ˌoff ˈcolor) adjective
1. not before noun (BrE, informal)not in good health; looking or feeling ill/sick
2. usually before noun (especially NAmE)an off-colour joke is one that people think is rude, usually because it is about sex