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頭の黒いネズミ (あたまのくろいネズミ) Japanese meaning | Kotomora
頭あたま の 黒くろ いネズミ also: あたまのくろいねずみ
Meanings 1
expression, noun
workplace thief ; embezzler ; untrustworthy person
Idiomatic expression literally meaning 'a rat with a black head', used to describe someone who steals money from their workplace or is generally untrustworthy. Often used in a derogatory or cautionary sense.
会かい
社しゃ
の
金かね
を
ちょろまかす
よう
な
頭あたま
の
黒くろ
いネズミ
は
許ゆる
せ
ない
。
I can't forgive a workplace thief who skims company money.
Written forms 頭あたま の 黒くろ いネズミ
Standard spelling with katakana for ネズミ, matching the primary reading.
頭あたま の 黒くろ い 鼠ねずみ
Kanji spelling for 鼠; less common but still used.
頭あたま の 黒くろ いねずみ
All-hiragana spelling; may be used for clarity or in informal writing.
あたまのくろいねずみ
Kanji 頭 head, counter for large animals Similar words 泥どろ 棒ぼう 猫ねこ 泥棒猫 (literally 'thieving cat') is a similar idiomatic term for a thief, but often implies a sneakier or more personal betrayal, while 頭の黒いネズミ specifically targets workplace embezzlement or untrustworthiness.
Etymology The phrase literally means 'a rat with a black head'. The exact origin is uncertain, but it likely plays on the image of a rat as a sneaky, thieving creature, with 'black head' possibly implying a hidden or deceitful nature. It is a set expression in modern Japanese.
