also: ふのう
noun
flotation device; life buoy; swimming float
Refers to any inflatable or buoyant device used to keep a person afloat, such as a life buoy, swimming ring, or water wings. Not limited to a specific shape.
子供は浮き袋をつけてプールで遊んでいる。
The child is playing in the pool wearing a swimming float.
船から落ちた人に浮き袋
They threw a life buoy to the person who fell from the boat.
noun
swim bladder; air bladder
The internal gas-filled organ that helps fish control buoyancy. In everyday contexts, 浮き袋 (うきぶくろ) is used; the technical term 浮嚢 (ふのう) appears mainly in biology.
See also: 鰾 (うきぶくろ)
魚の浮き袋は浮力を調節する役割がある。
A fish's swim bladder functions to regulate buoyancy.