カン, おちい.る, おとしい.れる

collapse, fall into, cave in, fall (castle), slide into

JLPT1 G7 S10 F1154

As per # (contain in a cavity) + 阜 piled earth → earthen object that collapses and sinks into a cavity → *fall*; *sink* → *ensnare*; *entrap*; *capture*; *pitfall*.

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