a special hole in the outside wall of a bank into which a customer can put money or documents safely when the bank is closed 夜间保险箱〔装在银行外墙上,供顾客在银行关门后存钱或投放文件〕SYN British English night safe
From Longman Business Dictionary
night depositoryˈnight deˌpositoryAmerican EnglishAmEBANKING
a special hole in the outside wall of a bank into which a customer can put money or documents when the bank is closedSYN BrE night safe