noun
chin; lower jaw; mentum
Anatomical term for the chin or lower jaw. In everyday language, あご is more common; おとがい is used in medical or formal contexts.
オトガイ神経は下唇とオトガイ部の感覚を支配する。
The mental nerve innervates the lower lip and the chin region.
解剖学の授業でオトガイ孔の位置を確認した。
We checked the location of the mental foramen in anatomy class.
noun
Rare, archaic or highly literary term for a talkative person. Not used in modern everyday speech.
古語では「おとがい」がおしゃべりな人を指すこともあった。
In old language, 'otogai' could refer to a chatterbox.
あご is the common everyday word for chin or jaw. おとがい is a formal anatomical term.
The origin is uncertain. The kanji 頤 is a Chinese character meaning chin or jaw, adopted for this word.