Where does “頭が切れる” come from?

頭が切れる (Japanese) comes from Japanese 頭, from Japanese ど- — super-.

頭が切れる (Japanese): to be sharp; to be keen; to be on the ball; to have a mind like a steel trap; to be clever

Definitions

  1. to be sharp; to be keen; to be on the ball; to have a mind like a steel trap; to be clever

Ancestry of “頭が切れる”, step by step

頭が切れる traces back through 3 separate lines of ancestry.

via Japanese

StepLanguageWordMeaning
1Japanesehead; the fontanelle part of the skull; the head...
2Japaneseど-super-

via Japanese

StepLanguageWordMeaning
1JapaneseIndicates the subject of a sentence; conjunction;...
2Finnish-nkaForms nouns, mainly bird names (in dialects) and some toponyms

via Japanese 切れる

StepLanguageWordMeaning
1Japanese切れるbe cut off, break, snap, burst, collapse; be cut,...
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