bookkeeper (n.)youdaoicibaDictYouDict[bookkeeper 词源字典]
also book-keeper, 1550s, from book (n.) + keeper. A rare English word with three consecutive double letters. Related: Bookkeeping, which is from 1680s in the sense "the work of keeping account books;" book-keep (v.) is a back-formation from 1886.[bookkeeper etymology, bookkeeper origin, 英语词源]