瀬
ライ, せ, いわた, がせ, しげ, せい, せっ
rapids, current, torrent, shallows, shoal
JLPT1 G7 S19 F1152
As per 賴# (sharp reduction) + 水 water → swift current accompanying a sharp reduction in the size of a river, stream or other conduit → *rapids*; *shallows*.
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