the eastern jackdaw
鸒 refers specifically to the eastern jackdaw, a type of bird. Its meaning is narrow and ornithological, without broader abstract extensions.
鸒 combines 與 (top) and 鳥 (bird, bottom). The exact historical development is uncertain, but it likely follows a phono-semantic pattern where 與 contributes the sound and 鳥 indicates a bird.
The top component 與 looks like a pair of hands lifting something, and the bottom is 鳥 (bird). Imagine lifting a bird to identify it as the eastern jackdaw.
For ヨ, picture a yo-yo dangling from the bird's beak: yo -> ヨ, and the jackdaw plays with it.
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