To be a 'bronno' or more commonly 'a derty bronno'.. is to be a chatty bastard.
Behaviour that is likely to trigger this particular insult includes picking and eating one's bogeys/earwax etc, eating or drinking something you 'found' on an empty table in a pub, or any other foul activity that might be expected of a scally.

Can be used semi-affectionately amongst the sort of very close friends who greet each other with a friendly 'alright cunt, not seen you in fucking time'.

Used in parts of North Nottingham.
"yer derty bronno"
"Wot you anging around with that filthy bronno for?"
by The Monk September 23, 2004
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