Translation

bibliomania (specific type) / book hoarding / unread book pile

Meaning

The act of buying books and letting them pile up unread, often with the intention of reading them later. It's a portmanteau of the Japanese words 'tsunde-oku' (to pile up things and leave them) and 'dokusho' (reading books). While it describes a common behavior, it doesn't necessarily imply a negative or obsessive compulsion, but rather a love for books and the aspiration to read more.

Examples

• I have a serious case of tsundoku; my bedside table is overflowing with unread novels.
  私は重度の積ん読です。ベッドサイドのテーブルは未読の小説であふれています。
• Many book lovers admit to tsundoku, finding joy in the mere possession of books, even if they don't get around to reading them immediately.
  多くの本好きが積ん読を認め、すぐに読まなくても本を所有すること自体に喜びを感じています。