tradesman's entrance
noun [ S ] UK old-fashioned uk/ˈtreɪdz.mənz ˌen.trəns/ us/ˈtreɪdz.mənz ˌen.trəns/
（旧时送货用的）后门
the side or back door of a large house, used, especially in the past, by people delivering goods who were not allowed to use the door at the front of the house
I've forgotten my front-door key, so we'll have to use the tradesmen's entrance. 我忘带了前门钥匙，因此我们只好从后门进屋。