swim bladder; air bladder
The gas-filled organ in fish that controls buoyancy. In everyday contexts, 浮き袋 is the usual term; 鰾 is a specialized or literary kanji.
See also: 浮き袋
魚のうきぶくろは浮力を調節する役割がある。
The swim bladder of a fish functions to regulate buoyancy.
鰾は魚類に特有の器官である。
The swim bladder is an organ unique to fish.
Common spelling for 'swim bladder' (also means 'floatation device').
The kanji 鰾 is composed of 魚 (fish) and 票 (sign, mark), but the historical derivation is uncertain. The reading うきぶくろ is a jukujikun meaning 'float bag'.