1 of 3

noun (1)

: the dross or scoria of a metal


2 of 3

noun (2)

chiefly British slang
: a lewd or promiscuous woman


3 of 3


slagged; slagging

transitive verb

chiefly British
: to criticize harshly

Examples of slag in a Sentence

Verb London reviewers slagged off the new play for being another kitchen-sink drama.
Recent Examples on the Web
According to York Archaeology, the blocks were cut from slag—a stony byproduct of smelting ore in a blast furnace, which was an important component of English industry in the 1800s. Sonja Anderson, Smithsonian Magazine, 2 May 2024 Real Alloy Recycling zero waste project Real Alloy Recycling in Wabash will receive $67.3 million to create a zero-waste salt slag recycling facility on the back of its existing aluminum recycling facility. Karl Schneider, The Indianapolis Star, 28 Mar. 2024 Reviewers are often so quick to slag movies that ask them to think, that a film like Adam Sandler’s sci-fi drama Spaceman forces them to reveal their idiocy. Armond White, National Review, 8 Mar. 2024 As the four-times indicted, twice impeached former president ping-pongs between court dates and campaign appearances, the latest lyrical slag from the veteran punk-pop trio was not a huge surprise. Gil Kaufman, Billboard, 2 Jan. 2024 The 9-mile Calumet Trail’s original slag surface, built in 1972 from Dune Acres to Michigan City’s western border, has deteriorated. Tim Zorn,, 17 Nov. 2021 Industrial wastes like fly ash and blast furnace slag have replaced cement in concrete at times. Carolyn Barber, Fortune, 13 July 2023 Co-founded in 2020 by former National Basketball Association player Rick Fox, the company uses a combination of brine from desalination plants and waste products from steel production called slag to create a new form of cement. Yusuf Khan, WSJ, 24 Aug. 2023 During the cleaning, one of the slag accumulations came loose, sprayed the area with molten slag and killed five people. Garfield Hylton, Orlando Sentinel, 19 Aug. 2022
This had more than local repercussions, as the enmity trailed all the way back to the Philippines, where relatives in the two families slagged one another off on social media. Han Ong, The New Yorker, 16 Oct. 2023 Jordan Mendoza Offenses finding footing early on in Creighton-SDSU The perimeter shooting from both teams slagged to start the game between No. 6 Creighton and No. 5 San Diego State, with both teams putting up an airball on three-point attempts on consecutive possessions. Lorenzo Reyes, USA TODAY, 26 Mar. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'slag.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Noun (1)

Middle Low German slagge

Noun (2)

earlier argot slag coward, worthless person


probably from slag entry 2

First Known Use

Noun (1)

1552, in the meaning defined above

Noun (2)

circa 1958, in the meaning defined above


1971, in the meaning defined above

Time Traveler
The first known use of slag was in 1552

Dictionary Entries Near slag

Cite this Entry

“Slag.” Dictionary, Merriam-Webster, Accessed 21 May. 2024.

Kids Definition


: waste left after the melting of ores and the separation of the metal from them

More from Merriam-Webster on slag

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