partridge
鷓 refers specifically to a partridge, a type of game bird.
鷓 combines 庶 (which likely contributes the sound) with 鳥 (bird), forming a phono-semantic compound for a type of bird, specifically the partridge.
The left side 庶 suggests a common or numerous bird, and the right side 鳥 confirms it is a bird. Picture a flock of partridges hiding among common undergrowth.
For シャ, imagine a partridge making a soft 'sha' sound as it rustles through the bushes: sha -> シャ.
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