Tsundoku

"Tsundoku" (n.) is the constant act of buying books, but never reading them. Specifically, it is letting books pile up in one's room so much that the owner never gets a chance to read all of them. This is done by the owners of the books, not by the booksellers. The origin of "Tsundoku" is a Japanese slang (積ん読) "tsun-doku". 「積ん読」 came from 「積んでおく」 "tsunde-oku" (to pile things up ready for later and leave) and 「読書」 "dokusho" (reading books). 「積んどく」 "tsundoku" is a euphonic change of 「積んでおく」. It is also used to refer to books ready for reading later when they are on a bookshelf.