grass which has been cut and re-grown, wild grass
芿 centers on grass that regrows after cutting, or wild grass more generally. The idea is persistent, untamed vegetation.
芿 combines the grass radical 艹 with 仍, which likely contributes the sound. The character is rare, and its exact historical development is uncertain.
The grass crown 艹 sits above 仍, like grass that keeps coming back after being cut. Picture a lawn that regrows stubbornly.
For ジョウ, imagine a gardener named Joe who keeps cutting the wild grass, but it always regrows: Joe -> ジョウ.
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