slag off

//slæɡ ɒf//insult

What does slag off mean? slag off is a English moderate that translates to “badmouth / trash-talk” in English.

to talk waste about

01

"badmouth / trash-talk"

To criticize or badmouth someone, usually behind their back. Different from 'slag' (the noun insult) — 'slagging off' is the act of speaking negatively about someone. 'Slagging' in Irish English can actually mean playful teasing between friends, which is a completely different vibe.

'He's always slagging off the boss behind her back.' Irish: 'The lads were slagging me about my haircut.'