oriole
鶊 refers specifically to the oriole, a type of bird.
鶊 combines 鳥 (bird) with 庚, which likely provides the sound. The character was created to name the oriole.
The right side is 鳥 (bird), and the left side 庚 looks like a bird perched on a branch. Together they point to a specific bird: the oriole.
For コウ, imagine an oriole singing a clear 'coo' sound: coo -> コウ, and the bird's call echoes through the trees.
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