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削    铁    如    泥    切削铁器如同斩剁泥土一样。形容兵刃极其锋利。 褒义>

削铁如泥是对宝刀宝剑锋利度的一个夸张的形容，表示刀剑切削铁器像切泥一样的容易。形容兵刃极其锋利。

Would cut clean through iron as though it were mud

削木为吏    削足适履    削发披缁    削趾适屦    削草除根