Cheap Sparkling Wine. In fact the cheapest sparkling wine at a bottlo, should only be purchased in the absence of passionpop at said bottle shop.
The term itself is a portmanteau of goon and champagne despite the fact that goonshagne will almost certainly never be from the champagne region of france.
Store Guy: Orrrr...Sorry we're out.
Underage Slut: Fuckin Fuck! I wanted to fuckin trash myself with it and get with six guys. Oh well i'll just take a few bottles of goonshagne, at least that stuff looks pretty classy.
Drunk reveler 1: Yes! I found a bottle of goonshagne in your mums cupboard!
Drunk reveler 2: Yeah, shes a closest alco...
Drunk reveler 1: oh...