Definition of slag in English:

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Pronunciation: /slaɡ/


1Stony waste matter separated from metals during the smelting or refining of ore.
Example sentences
  • The hardened matter was slag, a waste product from metal working, and contained evidence of iron, copper and lead manufacture.
  • In highly developed countries, the major components of industrial waste are blast furnace and steel slag, and power station ash.
  • The union has leveled 15 separate charges against Levy, a contractor at Mittal Steel USA, which performs slag processing and metal reclamation.
1.1Similar material produced by a volcano; scoria.
Example sentences
  • Thirdly, reduce the clinker content in cement, by intergrinding cementious material like slag, fly ash, or limestone.
  • The difference in densities of the molten iron and molten slag allow each material to be removed separately from the furnace.
  • It was a more rustic and northern version of Detroit with escarpments of slag and iron ore.
2British informal, derogatory A promiscuous woman.
Example sentences
  • Boys continued to make the same distinction between prospective wives and slags.
  • If you look beyond the dehumanising stereotypes to the hard facts, it emerges that females in jail are not conniving slags.
  • She told him Trev had called her a dirty slag after their drink the other night and had refused to sleep with her.

verb (slags, slagging, slagged)

[no object] (usually as noun slagging)
Produce deposits of slag.



adjective (slaggier, slaggiest)
Example sentences
  • The whole of it waggled with unhealthy cushions of fat; it all hung, it was all slack and without structure - slaggy, gelatinous, sick.
  • Everyone must have some sympathy with Bible Belters and Muslims who point to the slaggy decadence of secular western culture.


Mid 16th century: from Middle Low German slagge, perhaps from slagen 'strike', with reference to fragments formed by hammering.

  • Slag is from Middle Low German slagge, perhaps from slagen ‘strike’, with reference to fragments formed by hammering. From the sense of refuse developed a slang use meaning ‘worthless person’ in the late 18th century, which only developed the modern dominant sense ‘promiscuous woman’ in the mid 20th century. The verb sense ‘criticize’ as in slagged off, dates from the 1970s.

Words that rhyme with slag

bag, blag, brag, Bragg, crag, dag, drag, flag, gag, hag, jag, lag, mag, nag, quag, rag, sag, scrag, snag, sprag, stag, swag, tag, wag, zag

For editors and proofreaders

Syllabification: slag

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