こおん

noun

古音: an ancient pronunciation of a word / 鼓音: a drum-like sound, caused by percussion or tapping of the body during a medical examination

彼は古音を研究するのが好きです。

He likes to study ancient pronunciations.

意味（1）

古音: an ancient pronunciation of a word

意味（2）

鼓音: a drum-like sound, caused by percussion or tapping of the body during a medical examination