1/2 pr st
This rare kanji has no clear standalone meaning. The given gloss "1/2 pr st" is obscure and likely an abbreviation; treat its meaning as uncertain.
珷 combines 王 (jade) with 武, but the historical origin and original meaning are unclear. It may be a phono-semantic compound, but the exact development is uncertain.
The left side 王 suggests jade or a precious stone, and the right side 武 suggests martial strength. Picture a rare ceremonial jade weapon, but its exact use is forgotten.
For ブ, imagine a martial artist (武) holding a jade (王) bo staff: bo -> ブ.
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