What does "slag" mean?
Waste material from a mine.
Slag
/slæɡ/ noun, verb, slang
noun, verb, slang ·Common ·High school level
Meaning at a glance
- Primary sense: Waste material from a mine.
- Grammar: slag is listed as noun, verb, slang.
- Nearest alternatives: dross, alluvion, alluvium, ash.
- Useful contrasts: commend, compliment, extol.
- Usage evidence: Due to improper procedures, the foundry had an excess of slag in the crucible.
How to use "slag"
- Start with the primary definition, then check the part of speech before placing the word in a sentence.
- Compare nearby synonyms to make sure "slag" carries the exact meaning, tone, and strength you need.
- Use the example sentence as a context check. If your sentence uses the word differently, confirm that the grammar still fits.
Meaning check
- Does the word fit the sentence's grammar?
- Does it match the intended tone rather than only the dictionary definition?
- Would a simpler synonym be clearer for the reader?
- Is there enough surrounding context to prevent ambiguity?
Source and review context
This entry combines structured lexical data with WordToolSet review checks. Definitions, examples, synonyms, and usage notes may come from different source tables, so the page is designed to show evidence from more than one angle before you rely on "slag" in a final draft.
If a word has several senses, prefer the sense that matches your sentence's grammar and surrounding context. A correct definition can still be the wrong choice when the sentence needs a different register, emphasis, or level of specificity.
Before you rely on this definition
Read the first definition as a starting point, then check the example, synonyms, and part of speech before treating "slag" as the right word for your sentence.
If your draft is formal, technical, persuasive, or sensitive, compare "slag" with a nearby alternative so the final choice matches both meaning and reader expectation.
Compare nearby meanings
- Use synonyms when you need a softer, stronger, simpler, or more specific word.
- Use antonyms to check the boundary of the meaning and avoid accidental contrast.
- Use the example sentence to confirm the word behaves naturally in context.
- Keep the original wording when a replacement adds complexity without improving precision.
Definition decision workflow
1. Identify the role
Check whether "slag" is acting as noun, verb, slang in your sentence. A definition is only useful when the grammar matches the way the word is being used.
2. Test the nearest option
Compare it with "dross" and other nearby choices to see whether the sentence needs a softer, stronger, or more familiar word.
3. Confirm with context
Use the example sentence below as an evidence check, then read your own sentence out loud to catch tone or rhythm problems.
Review note: Definition pages are checked for source coverage, sentence evidence, synonym support, and editorial insight before they are treated as approval-ready pages. If the evidence is too thin, the page remains available to users but is kept out of the approval-facing indexed inventory.
Final meaning check
Before publishing a sentence with "slag", ask whether the word helps the reader understand the idea faster. A precise word should reduce confusion, not simply make the sentence look more polished.
When the definition, synonym evidence, and example context point in the same direction, the word is usually a safer choice. When they conflict, revise the sentence or choose a clearer alternative.
Definitions
Noun
- 1 Waste material from a mine. countable, uncountable
"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."
- 2 the scum formed by oxidation at the surface of molten metals wordnet
- 3 Scum that forms on the surface of molten metal. countable, uncountable
"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."
- 4 Impurities formed and separated out when a metal is smelted from ore; vitrified cinders. countable, uncountable
"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."
- 5 Hard aggregate remaining as a residue from blast furnaces, sometimes used as a surfacing material. countable, uncountable
"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)."
Show 4 more definitions
- 6 Scoria associated with a volcano. countable, uncountable
- 7 A prostitute or promiscuous woman; a slut. Australia, Ireland, UK, countable, derogatory, slang, uncountable
"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."
- 8 A coward. Ireland, UK, countable, dated, derogatory, uncountable
- 9 A contemptible person, a scumbag. Cockney, Ireland, UK, countable, derogatory, uncountable
"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."
Verb
- 1 To produce slag. transitive
- 2 convert into slag wordnet
- 3 To become slag; to agglomerate when heated below the fusion point. intransitive
- 4 To reduce to slag. transitive
- 5 To talk badly about; to malign or denigrate (someone). UK, slang, transitive
"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."
Show 2 more definitions
- 6 To make fun of; to take the piss (tease, ridicule or mock). Ireland, slang, transitive
- 7 To spit. Australia, intransitive, slang
Antonyms
Example
"Due to improper procedures, the foundry had an excess of slag in the crucible."
Common questions
What is a synonym for "slag"?
Common synonyms include: dross, alluvion, alluvium, ash, ashes, belittle.
How do you use "slag" in a sentence?
Due to improper procedures, the foundry had an excess of slag in the crucible.
How do you pronounce "slag"?
Pronounced /slæɡ/.
Etymology
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.