Somebody who was actually born in Manchester or lives in the city.
Manchester United Fans from London usually pretend that they are in some way related to Manchester and acuse
Manchester City fans (who are in most cases actually residents of the afore mentioned city) of being 'stupid, fucking inbred wankers' because their vocabulary doesn't really extend much further.
A Genuine Mancunian realises that
Manchester United aren't actually a Manchester team at all, while Manchester City are firmly at home within the boundaries of the actual city itself...