Mind your own business is a sharp refusal to explain yourself. Mind your own business, thank you.
It is genuinely rude, which is what separates it from never you mind. Between friends it can be softened into a joke, but the words themselves are not soft.
1phrasemind your own businessA sharp refusal to explain yourself.
“She told him to mind your own business and shut the door.”
mind your own business is a phrase.
Practised in Small Talk & Everyday Phrases