Slag is waste matter separated from metal during smelting.(noun)
An example of slag is the iron and silica that is removed during copper and lead smelting.
To slag is defined as to create waste matter from metal smelting.(verb)
An example of to slag is for the heat of copper smelting to remove the iron and silica from the copper.
See slag in Webster's New World College Dictionary
Origin: < MLowG slagge (> Ger schlacke) < slagen, to strike: for IE base see slay
See slag in American Heritage Dictionary 4
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