Poniewaz last name

My last name is Poniewaz which I know is a word in Polish but I was wondering if any of you know anything about the origins of my name because I can't find anything on it. Also as for Coat of Arms how can one go about tracing those back, I'm fairly sure my family doesn't have one but I've always been interested in symbolic heritage.

poniewaz = because

Hello

My last name is Poniewaz, too. I'm from Poland.