wash rice
淅 centers on washing rice, specifically the action of rinsing grains in water.
淅 combines 氵 (water) with 析, which likely contributes the sound セキ and the idea of separating or dividing, as rice is washed by separating it from impurities in water.
Water 氵 pours over the right side 析, like rinsing rice to separate the clean grains from the cloudy water.
For セキ, imagine washing rice in a second (セキ) sink: second -> セキ, and the water cleans the grains.
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