Dont feel dumb.Its a good question.I dont think there is a definition for it but to me street style is ....exactly that style you see on the streets. It dont come from runways or from the latest issue of vouge or glamour mag.It comes from your neighborhood.It's you own style..your own twist on fashion. Its your personality .That to me is what street style is. HTH
I agree with Dominicanbarbie..street style is undefined, because it's unique to the individuals you see on the streets, as opposed to the catwalk. That's just my opinion tho.