bioluminescent organ; photophore
Technical term in biology for light-producing organs found in deep-sea fish, fireflies, and other organisms.
深海魚の発光器は、獲物をおびき寄せるために使われる。
The photophores of deep-sea fish are used to lure prey.
Compound of 発光 (luminescence) and 器 (organ, device). The exact historical derivation is uncertain, but the term follows standard scientific naming patterns.