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Added 9 October 2026

slag

/ˈslæɡ/ noun

In Latin: scoria Wiktionary

noun Definition from Wiktionary (CC BY-SA). Pronunciation from Wiktionary, via Kaikki.org. More about slag at Wordnik → Where our words come from →

Waste material from a mine.
Scum that forms on the surface of molten metal.
Impurities formed and separated out when a metal is smelted from ore; vitrified cinders.

verb

To produce slag.
To become slag; to agglomerate when heated below the fusion point.
To reduce to slag.

Origin

Borrowed from Middle Low German slagge, slaggen (“slag, dross”), from Old Saxon *slaggo, from Proto-West Germanic *slaggō, from Proto-Germanic *slaggô, from Proto-Germanic *slagōną (“to strike”) + *-gô (diminutive suffix). Compare Middle Low German slāgen (“to strike”), since originally the splinters struck off from the metal by hammering, from *slagōn, from Proto-West Germanic *slagōn. Compare also Old Saxon slegi, from Proto-West Germanic *slagi. See also Dutch slak, German Schlacke, Swedish slagg; also compare English slay.

From Wiktionary, via Kaikki.org (CC BY-SA)

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