An former or current Eton (or other public school) pupil who is heavily into grime, dubstep or any other form of alternative street music/culture. Often characterised by obnoxious and expensive trainers, excessive drug use and an uncanny ability to be able to talk like Wiley among fellow streetonians whilst remembering their elocution lessons come through when asking Mummy for more money.
Tarquin: Hugo, bro, you're like ma fam nd ting.
Hugo: Dunknow, we been repping the dubstep hype since way back.
'Look at Victor in his snapback, what a streetonian'