garbage, refuse, waste
垃 centers on discarded material: garbage, refuse, or waste. It is a rare kanji used mainly in compounds for trash.
垃 is a modern character formed by combining 土 (earth/soil) with 立, likely as a phono-semantic compound where 立 hints at the sound and 土 suggests waste or soil. The exact historical development is uncertain.
The left side is 土 (earth/soil) and the right side is 立 (stand). Picture garbage standing on the ground, like a pile of waste on the soil.
For ラツ, imagine a rat rummaging through the garbage: rat -> ラツ, and the rat stands on the soil among the waste.
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