slagger
/ˈslæɡər/Definitions
1. noun
A person who habitually criticizes or speaks negatively about others, often in a sarcastic or mocking manner.
“The comedian was accused of being a slagger for his biting comments about politicians.”
2. verb
To criticize or speak negatively about someone or something, often in a sarcastic or mocking manner.
“She slagged off her colleague’s idea in front of the whole team.”