裏うら声ごえ

noun

falsetto

A singing or speaking voice produced in a high register, often used for effect or to reach high notes.

• 彼かれは裏うら声ごえで高こう音おんを出だした。

  He hit the high notes in falsetto.

• 裏うら声ごえを使つかうと、声こえが裏うら返がえる感かんじがする。

  When I use falsetto, my voice feels like it's cracking.