SumiTsundoku: the Japanese word for books you never read (積ん読)
Tsundoku (積ん読) is the pile of books you bought, meant to read and haven’t opened yet, and the habit of buying them anyway. The kanji are 積, pile up, and 読, read. It’s a joke word: it sounds like “pile it up and leave it”, but it’s written to look like a kind of reading.
What the kanji say
積 (seki, or tsumu) means to pile up or build up. The 禾 on its left is a stalk of grain, and in Chinese it can mean storing up the harvest; 責 on the right gives the sound. 積む (tsumu) is to stack or to load, and 積もる (tsumoru) is what snow and dust do.
読 (doku, or yomu) means to read. The 言 on its left is speech: the oldest meaning was to say something aloud or recite it, and only later to read. 読む (yomu) is to read, and 読書 (dokusho) is reading books.
An old pun
積んでおく (tsunde oku) means “to pile up and leave for later”. In casual speech it shrinks to 積んどく (tsundoku). Write that last part with 読 (doku), the reading it has in 読書, and the lazy phrase turns into 積ん読: a word that looks like a kind of reading but means not reading at all. That’s why it keeps a hiragana ん in the middle. You’ll also see it written 積読.
The joke goes back to slang of the Meiji era (1868–1912), so Japanese readers have had a word for this habit for well over a century. In English, tsundoku drew wide attention in the 2010s, in articles from the Los Angeles Times (2014) to the BBC (2018), often presented as a Japanese word with no English equivalent.
How to use it
積ん読がまた増えた。
Tsundoku ga mata fueta.
My pile of unread books has grown again.
この本はずっと積ん読になっている。
Kono hon wa zutto tsundoku ni natte iru.
This book has been sitting in my unread pile for ages.
今年こそ積ん読を減らしたい。
Kotoshi koso tsundoku o herashitai.
This year I really want to get through my unread pile.
買ったまま積んである本が多い。
Katta mama tsunde aru hon ga ooi.
I have lots of books I bought and just stacked up.
- It’s informal and a little self-mocking. People use it about their own shelves, with a smile.
- It can mean the habit or the books. 積ん読の山 (tsundoku no yama) is a mountain of unread books.
- It’s a noun. Things “become” tsundoku: 積ん読になる (tsundoku ni naru).
Words with the same kanji
| Word | Reading | Meaning |
|---|---|---|
| 積む | tsumu | to pile up, to load |
| 積もる | tsumoru | to pile up (snow, dust) |
| 面積 | menseki | area (size) |
| 読む | yomu | to read |
| 読書 | dokusho | reading books |
| 読者 | dokusha | reader |
Remember it
Stack the grain (積) high, put a book (読) on top, and leave it there. That’s tsundoku.
The kanji in this lesson
Tap Draw it to watch the stroke order. Numbers show where each stroke starts.