getting completely owned by someone
I just pewned ur ass!
U got pewned noob!
Im pewning so many noobs right now
Usualy used in online games when you completely destroy someone with no hope of them doing any damage back.
Usualy when someone experianced beats someone much less experianced hands down. Or (for example in eve-online) a fleet of ships takes on one person who clearly has no hope of winning against them. IE they will be/have been Pewned.