Question on the idiom 頭が回転しない


I found the following dialogue on lang-8:

A: 駄目だ、飲み過ぎて頭が回転しない。 B: 仕事、明日にしたら?

A: Oh no, I drank too much so I can't concentrate on it. B: Why not do your work tomorrow?

So does 頭が回転する mean "able to concentrate" or am I misunderstanding it? In English when ones head spins, it is a euphemism for being drunk or dizzy but I guess in Japanese having ones head revolve quickly (maybe describing the speed of thoughts turning over/ideas coming) equals being quick-witted. Would anyone be kind enough to explain this idiom?


Posted 2013-08-05T04:17:58.313

Reputation: 10 735



It's just based on the metaphorical idea of something turning meaning that something is functioning normally, as in a machine. In English we have sayings about the gears not turning. You can't really try to draw parallels between idiomatic phrases. For example, in English if you're dizzy then your head is spinning, but in Japanese it's your eyes that spin (目が回る).

Look, for example, here. Particularly at definition 3, which reads:

3 機能を十分生かした働きをすること。存分に活動すること。「頭の―が鈍い」「人員を―させて事務をさばく」

The definition of 回転 includes the idea of something 'moving' metaphorically in such a way that it fulfills its functions.


Posted 2013-08-05T04:17:58.313

Reputation: 18 611

Thank you for your effort, but why answer with an assumption? I appreciate the extra eye idiom, though. – yadokari – 2013-08-05T04:29:59.967

Mostly because I can't find anything anywhere that discusses the meaning. It's a fairly strong assumption so that's why I posted it, but if someone can offer a better answer then I invite them to do so. – ssb – 2013-08-05T04:38:09.270

4日本国語大辞典 says "...また、比喩的に次から次へと考えの及ぶこと...「頭の回転が早い」" for 回転, so it seems like a good explanation to me – cypher – 2013-08-05T07:47:44.743

Thanks for mentioning that. Though I can't seem to find that particular entry online I did look at another place and found a mention. – ssb – 2013-08-05T08:29:19.537

Ever heard the phrase "hamster's running but the wheel's not turning"? – nkjt – 2013-08-05T12:01:32.937

@nkjt, no but i have heard the phrase, " a sleeping yak swims without a wetsuit." – yadokari – 2013-08-05T18:08:03.067

Well, I don't know about yaks, but the hamster one is a colourful English metaphor equivalent of the Japanese (maybe not standard English, I never know when I'm using localisms) – nkjt – 2013-08-06T10:19:25.123