1 B2 idiomatic informal
To speak about someone in a rude or unkind way, typically behind their back.
"She spent half the lunch break slagging off her manager to the other staff."
separable
slag off
B2 informal separable transitive
To criticize or say rude, unkind things about someone or something, usually behind their back.
In plain English
To say nasty or mean things about someone, often when they are not there.
What does "slag off" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 B2 idiomatic informal
To harshly criticize a product, film, book, or idea.
"Critics have been slagging off the film since it was released last week."
separable
Usage tip
Distinctly British English. Considered fairly rude. Common in everyday speech among young people. The word 'slag' on its own is a strong insult in British English, but 'slag off' has become a standard informal expression for harsh criticism.
Words that pair with "slag off"
Natural word combinations native speakers use most often.
boss ex colleague celebrity film behind someone's back
How to conjugate "slag off"
The five tense forms you'll use most often.
Base
slag off
I/you/we/they
3rd person
slags off
he/she/it
Past simple
slaged off
yesterday
Past participle
slaged off
have + pp
-ing form
slaging off
continuous
Hear "slag off" in the wild
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