slug, snail
蝓 centers on a slow, soft-bodied mollusk: a slug or snail. The two given meanings are essentially the same creature, with 'snail' being the shelled variant.
蝓 combines 虫 (insect/creature) with 俞, which likely provides the sound ユ. The character was created to represent a slug or snail, a small crawling creature.
The left side 虫 indicates a small crawling creature, and the right side 俞 looks like a slimy body with a shell-like top. Picture a slug or snail slowly inching along.
For ユ, imagine a slug saying 'you' as it looks at you with its tiny eye stalks: you -> ユ, and the slug is the creature 蝓.
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