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to boil (something in hot water)
to treat with medicinal steam (a swelling, etc.)
卵を十分ほど煠でて固ゆでにした。
I boiled the eggs for about ten minutes to make them hard-boiled.
パスタを煠でる時間を計っている。
I'm timing how long to boil the pasta.
大きな鍋で枝豆を煠でて塩をかけた。
I boiled edamame in a big pot and sprinkled salt on them.