tall (7 chi) horse
騋 refers specifically to a tall horse, measured as seven chi in height. The meaning is narrow and concrete, without broader abstract extensions.
騋 combines 馬 (horse) with 來, which likely contributes the sound ライ. The character was created to denote a specific tall horse.
The left side 馬 is a horse, and the right side 來 suggests something coming or arriving. Imagine a tall horse arriving, its height measured at seven chi.
For ライ, picture a tall horse lying down: lie -> ライ, and the horse's height is measured while it rests.
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