寝ね耳みみ

noun

something heard while sleeping

Refers to information or sounds perceived during sleep, often used in the idiom 寝耳に水 (a bolt from the blue).

• その知しらせは寝ね耳みみに水みずだった。

  The news came as a complete surprise.

• 寝ね耳みみに水みずの話はなしで、しばらく言こと葉ばが出でなかった。

  It was such a bolt from the blue that I was speechless for a while.