mantis, dung beetle, insect
蜋 centers on insects, specifically a mantis or a dung beetle. The meanings are linked by being types of insects, with no broader abstract connection.
蜋 combines 虫 (insect) with 良, which likely contributes a phonetic element. The exact historical development is uncertain.
The insect radical 虫 on the left pairs with 良 on the right. Picture a mantis or dung beetle with a good (良) reputation among insects.
For ロウ, imagine a mantis rowing a tiny boat: row -> ロウ, and the insect rows away.
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