pool, puddle
瀦 centers on a small, still body of water: a pool or puddle, often one that forms naturally in a depression.
瀦 combines the water radical 氵 with 豬, which likely contributes the sound and may relate to a pig wallowing in water, suggesting a muddy pool. The exact historical development is uncertain.
Water 氵 plus a pig 豬: imagine a pig happily wallowing in a shallow pool of water, creating a muddy puddle.
For チョ, picture a pig named Cho splashing in the pool: Cho -> チョ, and the pig makes the puddle.
—