kind of large waterfowl with red
鸑 refers to a specific kind of large waterfowl, noted for having red coloring. The meaning is narrow and descriptive, without a broader conceptual center.
鸑 is a phono-semantic compound: 鳥 (bird) provides the meaning, while 獄 likely contributes the sound ガク. The exact historical development is uncertain.
The top part 獄 suggests a prison, and the bottom 鳥 is a bird. Imagine a large red waterfowl kept in a special enclosure, its red feathers standing out against the bars.
For ガク, picture a large red waterfowl honking with a deep 'gak' sound as it swims: gak -> ガク.
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