centipede, grasshopper
蚣 centers on long, many-legged crawling creatures: centipedes and grasshoppers. The two meanings are linked by the shared insect-like body plan and movement.
蚣 combines 虫 (insect) with 公, which likely contributes the sound. The character is used for specific arthropods like centipedes and grasshoppers.
The insect radical 虫 on the left pairs with 公 on the right. Picture a public (公) insect (虫) that everyone notices: a long centipede or a jumping grasshopper.
For コウ, imagine a centipede crawling into a public park (公園, こうえん). The コウ from こうえん cues the reading while the insect radical ties it to the meaning.
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