concha
Anatomical term for a shell-shaped structure, especially in the ear (耳甲介) or nose (鼻甲介). Rarely used alone; almost always appears in compound terms.
The concha is part of the outer ear and plays a role in collecting sound.
鼻甲介の腫れが鼻づまりの原因になることがある。
Swelling of the nasal concha can cause nasal congestion.
From the kanji 甲 (shell, armor) and 介 (shell, mediate), likely a direct translation of the Latin 'concha' (shell). The exact historical derivation is uncertain.