grey
駽 centers on the color grey, specifically referring to a grey horse. The meaning is narrow and concrete, with no clear abstract extensions.
駽 combines 馬 (horse) with 肙, which likely contributes the sound. The character was created to denote a grey horse.
A horse (馬) with a distinctive right side (肙) that looks like a small creature or worm: imagine a grey horse with a worm-like marking on its coat.
For ケン, picture Ken (a common name) riding a grey horse: Ken -> ケン, and the horse is grey.
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