gambling game with dice
蒱 refers specifically to a gambling game played with dice. Its meaning is narrow and does not extend to general gambling or games.
蒱 combines the grass radical 艹 with 捕, which likely provides the sound. The exact historical development is uncertain, but the character is associated with a specific dice game.
Picture grass 艹 covering a hidden dice game 捕: under the grass, people are secretly playing the gambling game 蒱.
For ホ, imagine a gambler whispering 'ho!' in excitement when the dice land favorably in the grass-hidden game: ho -> ホ.
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