noun
slag
SLAG
noun
1
Waste material left over after smelting ore.
"Heaps of slag from the old ironworks still cover the hillside."
verb
1
(British, informal) To criticise or mock someone harshly.
"The critics slagged off the film for its weak script."
How to Use Slag
Learner’s notesIn plain EnglishLeftover waste from melting metal ore — or, informally in Britain, to badmouth someone.
When to use it
The "criticise" sense ("slag off") is informal British slang; the noun as a term for a person is vulgar and should be used with care.
Common pairings
slag off
slag heap
Word Forms
slagged past tense, slags plural, slags singular
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Heaps of _____ from the old ironworks still cover the hillside.
Etymology
Borrowed from Middle Low German slagge, related to a Germanic root for "to strike" — originally referring to metal splinters knocked off during hammering.