A badass party where people who aren't hosting the party can invite whoever they want. It often involves a lot of alcohol, and the parties are often held through a house or large venue that doesn't necessarily belong to the host.
"I'm going to Nina's banger tonight, so I have to bring as much booze as possible."
"Someone snitched and called the police to break up the banger last night."
A specific type of hangover which involved getting drunk and resulting in a hook up. The endorphins from sexy timesoffset the pain of hangover meaning you feel undeservedly fantastic!
Friend: We drank so much last night, how are you coping?
Me: Pretty great actually; I got laid so have a bangover today
Friend: Nice work *high five*