Definition of no you don't in English:
no you don't
phrase
informal Used to indicate that one intends to prevent someone from doing what they were about to do.
- ‘Sharon went to get in the taxi. “Oh no you don't,” said Steve’
- ‘No you don't lad. Let William and Jack go after them.’
- ‘‘Oh no you don't!’ I shouted, jumping for the door before he could.’