slag

S1L1A1G2
US, UK/ˈslæɡ/British, Northern England, Scotland, Southern, Standard, Wales/ˈslaɡ/Australia/ˈslæ(ː)ɡ/New Zealand/ˈslɛɡ/

noun

Waste material from a mine.

Less commonScrabble 5

Meanings

nounslag (countable and uncountable, plural slags)

plural slags

  1. countableuncountableWaste material from a mine.

    After the big village, the scenery had returned to grass and woodland, but this had now given way to ugly mounds of discarded slag. Beyond the slag was a colliery with its machinery and smoking chimney, making the whole area look grim and austere.

    2011, Vivienne Dockerty, A Woman Undefeated, page 54

    Synonyms: goafing, gobbin, mullock

  2. countableuncountableScum that forms on the surface of molten metal.

    He leans out over the track and skims slag off the top of the boiling steel, risking what is called “catching a flyer,” which occurs when hot metal explodes out of the mold, spraying everyone in the vicinity.

    2009, John Hoerr, Monongahela Dusk, page 255
    1 more example

    2006, Melisa W. Lai, Michele Burns Ewald, Chapter 95: Silver, Martin J. Wonsiewicz, Karen G. Edmonson, Peter J. Boyle (editors), Goldfrank′s Toxicologic Emergencies, 8th Edition, page 1358, In Asia Minor and on islands in the Aegean Sea, dumps of slag (scum formed by molten metal surface oxidation) demonstrate that silver was being separated from lead as early as 5000 BC.

    Synonyms: dross

  3. countableuncountableImpurities formed and separated out when a metal is smelted from ore; vitrified cinders.

    Consequently, mounds of large ‘cakes’ of slag are often found near the smelting sites of the Late Bronze Age, as for example at Ramsau in Austria (Doonan et al. 1996).

    2008, Barbara S. Ottaway, Ben Roberts, “The Emergence of Metalworking”, in Andrew Jones, editor, Prehistoric Europe: Theory and Practice, page 207
    1 more example

    Buried within the Mediterranean littoral are some seventy to ninety million tons of slag from ancient smelting, about a third of it concentrated in Iberia. This ceaseless industrial fueling caused the deforestation of an estimated fifty to seventy million acres of woodlands.

    2006, Edwin Black, chapter 2, in Internal Combustion

    Synonyms: dross, recrement, scoria

  4. countableuncountableHard aggregate remaining as a residue from blast furnaces, sometimes used as a surfacing material.

    All these properties are determined by slag composition and its temperature. In basic slags, foaming ability increases as SiO₂ concentration grows.

    2010, Yuri N. Toulouevski, Ilyaz Y. Zinurov, Innovation in Electric Arc Furnaces, Springer, page 16
    1 more example

    During blast furnace operations, the plant operator pays careful attention to the slag chemistry (both composition and variability) as slag behavior is a major consideration in ensuring the quality of hot metal (molten iron).

    2006, Jan R. Prusinski, “44: Slag as a Cementitious Material”, in Joseph F. Lamond, James H. Pielert, editors, Significance of Tests and Properties of Concrete and Concrete-Making Materials, page 517

    Synonyms: clinker

  5. countableuncountableScoria associated with a volcano.

    Synonyms: clinker

  6. AustraliaIrelandUKcountablederogatoryslanguncountableA prostitute or promiscuous woman; a slut.

    2002, Josephine Cox, The Woman Who Left, 2012, ebook, unnumbered page, ‘Slag! Wait till I tell Jacob what we′ve been doing – and I will, you mark my words! He′ll want nowt to do with you then, will he, eh? He′ll see you for what you really are. A cheap and nasty little bitch!’

    5 more examples

    1984, Tristan Jones, Heart of Oak, 1997, paperback edition, page 260, We never talked about that, of course; we talked about how we could find a woman in the Dilly, and if the Yanks had taken them all, how we could always resort to the peroxided older slags who hung out around the side doors to Waterloo station and did knee tremblers for the Yanks.

    Which grotesque auld hing-oot will the shrivelled post-menopausal slag want tae shaft? Stay tuned.

    1994 [1993], Irvine Welsh, Trainspotting, London: Minerva, →ISBN, page 252

    ‘[…]He was a lovely man but, when I told him I wanted to continue swinging, he freaked out and called me a slag.’

    2008, Ashley Lister, Swingers - Female Confidential, page 31

    ‘[…]To the lady that came in to my coffee shop today and ripped on me and my fellow employees for being too slow: eat shit, you miserable slag!’

    2010, The Coast, Halifax, Canada

    Soph, yeah, you can't murk me / You're a slag, riddled with STDs

    2016 December 3, Millie B, “Soph Aspin Send”, performed by Millie B

    Synonyms: hussy, skank, NB: All terms are usually pejorative unless stated otherwise., 304, alley cat, alleycat, amorette, amoret

  7. IrelandUKcountabledatedderogatoryuncountableA coward.

    Synonyms: chicken, quakebuttock, bottler, caitiff, candy-ass, candy-arse, coistril, coward

  8. CockneyIrelandUKcountablederogatoryuncountableA contemptible person, a scumbag.

    Kill him. Kill the royal slag.

    1996, Sarah Kane, “Phaedra's Love”, in Sarah Kane: Complete Plays, published 2001, Scene 8, page 100
    3 more examples

    The writers took it for granted that England, with its working class composed of slags, purple-nosed losers, and animals fed on pinball, pornography and junk-food, was disintegrating into terminal class-struggle.

    1990, Hanif Kureishi, The Buddha of Suburbia, London; Boston: Faber and Faber, →ISBN, page 207

    The sycophantic slags all say / "I knew him first, and I knew him well"

    1987, “Paint a Vulgar Picture”, in Morrissey (lyrics), Johnny Marr (music), Strangeways, Here We Come, performed by The Smiths

    Can't believe it's been nearly 11 years since them slags smashed into the twin towers

    2012 September 13, Alexis Petridis, quoting Danny Dyer (tweet), “Danny Dyer: why them 9/11 slags are freaking his nut”, in The Guardian

    Synonyms: arsehole, prick, arsehole, ass, assface, asshat, asshole, asswipe

verbslag (third-person singular simple present slags, present participle slagging, simple past and past participle slagged)

present singular third person slags · participle present slagging · participle past slagged · past slagged

  1. transitiveTo produce slag.
  2. intransitiveTo become slag; to agglomerate when heated below the fusion point.
  3. transitiveTo reduce to slag.
  4. UKslangtransitiveTo talk badly about; to malign or denigrate (someone).

    If you slag off the other person, then—to the extent that your child identifies with that person as their parent—you are slagging off a part of them.

    2010, Courtenay Young, Help Yourself Towards Mental Health, page 344
    1 more example

    Rather than wait for her to start slagging my mother, I would disappear for a couple of days and inevitably, because I was getting no love at home, I began to stray once again.

    2011, John Davies, Slings and Arrows, page 109

    Synonyms: abuse, insult, slag off, diss, libel, slander, abuse, affront

  5. IrelandslangtransitiveTo make fun of; to take the piss (tease, ridicule or mock).

    Synonyms: befool, kid, take the piss, befool, chaff, disparage, forgab, frump

  6. AustraliaintransitiveslangTo spit.

    Synonyms: expectorate

Synonyms & antonyms

nounWaste material from a mine.

nounScum that forms on the surface of molten metal.

Similar

nounImpurities formed and separated out when a metal is smelted from ore; vitrified cinders.

nounHard aggregate remaining as a residue from blast furnaces, sometimes used as a surfacing material.

Similar

nounScoria associated with a volcano.

Similar

nounA prostitute or promiscuous woman; a slut.

verbTo spit.

More synonyms by meaning

nounthe scum formed by oxidation at the surface of molten metals

Broader

Synonym sets from Open English WordNet, CC BY 4.0.

Origin

  1. Proto-Germanic*slagōną“to strike”
  2. Proto-Germanic*slaggô
  3. Proto-West Germanic*slaggō
  4. Old Saxon*slaggo
  5. Middle Low Germanslagge
  6. Englishslag

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.

Full word history & related roots →

Translations

Ancient Greek σκωρία
  • σκωρία (skōría)the impurities which result and are separated out when melting a metal or refining it from its ore
Arabic خابث, خباث
  • خابثthe impurities which result and are separated out when melting a metal or refining it from its ore
  • خباثthe impurities which result and are separated out when melting a metal or refining it from its ore
Bulgarian шлака, застинала лава
  • шлака (šlaka)the impurities which result and are separated out when melting a metal or refining it from its ore
  • застинала лаваthe scoria of a volcano
Catalan escòria, dona fàcil
  • escòriathe impurities which result and are separated out when melting a metal or refining it from its ore
  • dona fàcila woman (sometimes a man) who has loose morals relating to sex
  • escòriathe scoria of a volcano
Chinese Mandarin 礦渣 /矿渣, 火山渣
  • 礦渣 /矿渣 (kuàngzhā)waste material from a mine
  • 火山渣 (huǒshānzhā)the scoria of a volcano
Czech struska, škvára
  • struskathe impurities which result and are separated out when melting a metal or refining it from its ore
  • škvárathe impurities which result and are separated out when melting a metal or refining it from its ore
Danish slagge
  • slaggethe impurities which result and are separated out when melting a metal or refining it from its ore
Dutch slak, del
  • slakthe impurities which result and are separated out when melting a metal or refining it from its ore
  • dela woman (sometimes a man) who has loose morals relating to sex
Finnish kuona, slagi
  • kuonathe impurities which result and are separated out when melting a metal or refining it from its ore
  • slagithe impurities which result and are separated out when melting a metal or refining it from its ore
  • huoraa woman (sometimes a man) who has loose morals relating to sex
  • lutkaa woman (sometimes a man) who has loose morals relating to sex
  • hutsua woman (sometimes a man) who has loose morals relating to sex
  • laavakivithe scoria of a volcano
  • mustamaalatato talk badly about someone; to denigrate someone
  • loatato talk badly about someone; to denigrate someone
  • puhua pahaato talk badly about someone; to denigrate someone
  • tuottaa kuonaato make slag
French scorie, pute
  • scoriethe impurities which result and are separated out when melting a metal or refining it from its ore
  • putea woman (sometimes a man) who has loose morals relating to sex
  • scoriethe scoria of a volcano
German Abraum, Schlacke
  • Abraumwaste material from a mine
  • Schlackethe impurities which result and are separated out when melting a metal or refining it from its ore
  • Schlampea woman (sometimes a man) who has loose morals relating to sex
  • Schlackethe scoria of a volcano
  • Lavathe scoria of a volcano
  • Schweißschlackethe scoria of a volcano
  • Auswurfthe scoria of a volcano
  • Auswurfmaterialthe scoria of a volcano
  • Schlackenstoffethe scoria of a volcano
  • Lavafetzenthe scoria of a volcano
  • Pyroklastikathe scoria of a volcano
  • herziehen überto talk badly about someone; to denigrate someone
  • schlecht machento talk badly about someone; to denigrate someone
  • verschlackento make slag
Hebrew סיגים
  • סיגים (sigím)the impurities which result and are separated out when melting a metal or refining it from its ore
Hungarian salak
  • salakthe impurities which result and are separated out when melting a metal or refining it from its ore
Icelandic gjall
  • gjallthe scoria of a volcano
Italian scorie, scoria
  • scoriethe impurities which result and are separated out when melting a metal or refining it from its ore
  • scoriathe impurities which result and are separated out when melting a metal or refining it from its ore
  • lavathe scoria of a volcano
  • magmathe scoria of a volcano
Latin scoria
  • scoriathe impurities which result and are separated out when melting a metal or refining it from its ore
Māori whaipara, rangitoto
  • whaiparathe impurities which result and are separated out when melting a metal or refining it from its ore
  • rangitotothe scoria of a volcano
  • kaihauthe scoria of a volcano
  • rahotothe scoria of a volcano
Norwegian slagg, sinder
  • slaggthe impurities which result and are separated out when melting a metal or refining it from its ore
  • sinderthe impurities which result and are separated out when melting a metal or refining it from its ore
  • luddera woman (sometimes a man) who has loose morals relating to sex
Polish żużel, szlag
  • żużelthe impurities which result and are separated out when melting a metal or refining it from its ore
  • szlagthe impurities which result and are separated out when melting a metal or refining it from its ore
  • dziwkaa woman (sometimes a man) who has loose morals relating to sex
  • puszczalskaa woman (sometimes a man) who has loose morals relating to sex
  • żużelthe scoria of a volcano
  • scoriathe scoria of a volcano
Portuguese escória, escória
  • escóriathe impurities which result and are separated out when melting a metal or refining it from its ore
  • escóriathe scoria of a volcano
Romanian zgurifica
  • zgurificato make slag
Russian шлак, ока́лина
  • шлак (šlak)the impurities which result and are separated out when melting a metal or refining it from its ore
  • ока́лина (okálina)the impurities which result and are separated out when melting a metal or refining it from its ore
  • шлю́ха (šljúxa)a woman (sometimes a man) who has loose morals relating to sex
  • шлак (šlak)the scoria of a volcano
Spanish escoria, telilla
  • escoriathe impurities which result and are separated out when melting a metal or refining it from its ore
  • telillathe impurities which result and are separated out when melting a metal or refining it from its ore
  • escoriathe scoria of a volcano
  • rajar deto talk badly about someone; to denigrate someone
  • cuerearto talk badly about someone; to denigrate someone
Swedish slagg
  • slaggthe impurities which result and are separated out when melting a metal or refining it from its ore
Thai ขี้เชื่อม, ขี้ตะกรัน
  • ขี้เชื่อม (kêe chêuam)the impurities which result and are separated out when melting a metal or refining it from its ore
  • ขี้ตะกรัน (kêe dtàgran)the impurities which result and are separated out when melting a metal or refining it from its ore
Ukrainian шлак
  • шлак (šlak)the impurities which result and are separated out when melting a metal or refining it from its ore
Vietnamese xỉ
  • xỉthe impurities which result and are separated out when melting a metal or refining it from its ore

Rhymes & wordplay

Rhymes with slag

All rhymes →

Anagrams

Cite this entry
APA

slag. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/slag

MLA

“slag.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/slag. Accessed November 2, 2026.

Chicago

WatkinsX Dictionary, s.v. “slag,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/slag.

Source: slag on Wiktionary, CC BY-SA 4.0.