slag
1 Americannoun
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Also called cinder. the more or less completely fused and vitrified matter separated during the reduction of a metal from its ore.
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the scoria from a volcano.
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waste left over after the re-sorting of coal.
verb (used with object)
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to convert into slag.
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Metallurgy. to remove slag from (a steel bath).
verb (used without object)
noun
noun
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Also called: cinder. the fused material formed during the smelting or refining of metals by combining the flux with gangue, impurities in the metal, etc. It usually consists of a mixture of silicates with calcium, phosphorus, sulphur, etc See also basic slag
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a mass of rough fragments of pyroclastic rock and cinders derived from a volcanic eruption; scoria
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a mixture of shale, clay, coal dust, and other mineral waste produced during coal mining
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slang a coarse or dissipated girl or woman
verb
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slang (tr) (usually foll by off) to abuse (someone) verbally
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slang (intr) to spit
Usage
What else does slag mean? Content warning: the following content includes references to strong and sexist language. In slang, slag is an insulting British English term for a contemptible person. When used of women, it can be equivalent to slut. As a verb, to slag (off somebody) is "to attack (them) verbally," i.e., to talk smack about them.
Other Word Forms
Etymology
Origin of slag1
1545–55; < Middle Low German slagge; cognate with German Schlacke dross, slag; see slack 2
Origin of slag2
First recorded in 1780–90; originally an argot word for a worthless person or a thug; perhaps identical with slag 1
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The Alabama-based aggregates company Vulcan Materials - once known as Birmingham Slag Co. - has no experience at doing either, and would just like to continue mining gravel.
From Washington Times • Apr. 27, 2022
He introduced her to the gallerist Irina Protopopescu, who put her work in an exhibition, “Absent Present,” at Slag Gallery in Chelsea in 2011, a year after she graduated.
From New York Times • May 15, 2020
Which brings us to “Modern Non-Binary Slag Harvest Time”, a concept introduced by singer and musician Shy Charles in a September Instagram post.
From The Guardian • Oct. 5, 2019
Slag has become a popular additive because it is a recycled material and enhances the sidewalk’s strength.
From Washington Post • Aug. 30, 2015
Slag looks like pieces of porous rock but actually is the cinders left over when iron ore is melted down to make steel.
From "Flying to the Moon: An Astronaut's Story" by Michael Collins
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.