Definition of don't start (or don't you start) in US English:

don't start (or don't you start)

phrase

informal
  • Used to tell someone not to grumble or criticize.

    ‘don't start—I do my fair share’
    • ‘Lenni corrected, rolling her eyes, ‘So don't you start.’’
    • ‘Your mom's already gonna kick your dad out for it, don't you start too.’
    • ‘Sarah turned her head to glare at her teenage son, ‘Joe, don't you start with me!’’
    • ‘‘Now don't you start,’ Briar replied, nudging Althia a second time and crying out when she shoved him in return.’
    • ‘I've been keeping the conversation moving so Buffy here doesn't blubber, so don't you start or we'll be having to blow dry my dress.’
    • ‘I contributed my archery skills, keen senses and prettiness to the Company, so don't you start.’
    • ‘Oh don't you start as well I've already had this conversation with Em and Casey today, yes I like Jonathan but as a friend nothing else, okay.’
    • ‘‘Oh don't you start,’ Arcadia said.’