漸
ゼン, やや

steadily, gradually advancing, finally, barely

JLPT1 G7 S14 F2115

As per 斬# (cut) + 水 water → partially cut the flow of water (compare 澀/渋 and 減) penetrating a crevice (compare 浸) → *gradual* (← partial/gradual cut) → *gradually*.

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