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overflowing; flood; inundation; deluge
oversupply; plethora; abundance (esp. of something undesirable)
台風の影響で各地の河川が汎濫した。
Rivers in various areas flooded due to the effects of the typhoon.
安価な模倣品が市場に汎濫して問題になっている。
The market is flooded with cheap imitation products, which has become a problem.
過剰な広告が街中に汎濫している光景は異様だ。
The sight of excessive advertising flooding the streets is unusual.