This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
駚 combines 馬 (horse) with 央, which likely contributes the sound. The exact historical development is uncertain, and the character is rare.
The left side is a horse 馬, and the right side is 央. Since the meaning is unclear, picture a horse standing in the center (央) of a field, but its purpose is unknown.
For ヨウ, imagine a horse yo-yoing back and forth in the center: yo -> ヨウ, and the horse 馬 stays near 央.
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