noun
waterfowl sleeping while floating on water
A poetic or literary term for ducks, geese, or other water birds that rest on the water's surface, often evoking a tranquil winter scene.
冬の池に浮寝鳥が静かに浮かんでいる。
On the winter pond, waterfowl are quietly floating asleep.
水鳥 is the general term for waterfowl, while 浮寝鳥 specifically refers to those sleeping on the water, often used in poetry.
Compound of 浮き寝 (ukine, 'sleeping while floating') + 鳥 (tori, 'bird'). The exact historical derivation is uncertain, but the word is conventionally associated with the image of waterfowl resting on the water.