Slag

v. form into slag

n. residue of ore separated from a metal during the smelting process; scoria, cinder-like pieces of lava (Geology)

For slang usage, see Slag (slang). Slag is also an early play by David Hare. For the Transformers character, see Slag (Transformer).Slags are the by-product of smelting ore to purify metals. They can be considered to be a mixture of metal oxides; however, they can contain metal sulfides and metal atoms in the elemental form. While slags are generally used as a waste removal mechanism in metal smelting, they can also serve other purposes, such as assisting in smelt temperature control and minimizing re-oxidation of the final liquid metal product before casting.
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Noun
1. the scum formed by oxidation at the surface of molten metals
(synonym) scoria, dross
(hypernym) scum
(hyponym) basic slag

n. blow, shot, cuff, hit, pelt, slash, knock, impact, kick, knack, chop, fib, swat, swipe, wallop, walloping, whack, whacking, whang, bump, crack, bang, bash, hammerblow, battle, scuffle, smite, slap, clap, percussion, punch, peal, tact, stroke

(v. t.)
The scoria of a volcano.
  

(v. t.)
The dross, or recrement, of a metal; also, vitrified cinders.