猫を被る
(Neko wo kaburu; “To play the cat”)

Definition:

To hide one’s true (wild or willful) nature and pretend to be quiet and obedient. Alternately, to pretend not to know about a situation that one is actually involved in or aware of. Used in a negative sense to convey duplicity.

Breakdown:

This verb phrase comprises a noun – 猫 (neko), “cat,” the object-marker particle を (wo), and the verb 被る (kaburu). The latter often refers to the act of wearing something on one’s head, giving this idiomatic expression a cute mental image. The verb also has a surprising range of more-or-less related meanings, among them “to be similar” or “to act like.”

Notes:

This idiom can take the form of a verb phrase, as above, but it can also appear as the noun phrase 猫被り (neko-kaburi).

Some scholars theorize that neko in this phrase is actually a corruption of 寝茣蓙 (negoza), a sleeping mat of woven rushes. In this theory, the image is not one of affecting the quiet nature of a cat, but of pulling a sleeping mat over oneself.

Example sentence:

「あいつ、いつも人を虐めてるくせに、先生が来るとすぐ猫を被るなんて、もううんざりだ！」

(“Aitsu, itsumo hito wo ijimeteru kuse ni, sensei ga kuru to sugu neko wo kaburu nante, mou unzari da!”)

[“That jerk, he’s always bullying people, but he acts all innocent as soon as the teacher comes. I’m fed up!”]

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