口くちを拭ぬぐう

expression, godan verb (-u)

feign innocence; play dumb

Idiomatic expression literally meaning 'wipe one's mouth'; used when someone pretends not to know about something they were involved in, like a child sneaking food and wiping their mouth to hide the evidence.

• 彼かれは知しっているくせに、口くちを拭ぬぐうように「何なにも知しらない」と言いった。

  Even though he knew, he said 'I don't know anything' as if feigning innocence.

expression, godan verb (-u)

wipe one's mouth

Literal meaning of the phrase; simply wiping one's mouth after eating or drinking.

• 食しょく事じの後あと、ナプキンで口くちを拭ぬぐった。

  After the meal, I wiped my mouth with a napkin.