(wîrd)(ás)(pärté)
n. pl. weird ass par·ties
def: A social gathering for pleasure or amusement, focusing on or celebrating the strange or otherwise out of the ordinary; rectum, behind, bum, rump, gluteus maximus, dumper or posterior.
The type of ass that is sought after in a club, party, or bar for grinding on, grabbing, or just looking at, but is a tad too big in a more sobering setting.
After a fun filled evening of gorging yourself on alcholic beverages you may suffer from party ass, a feeling of heaveyness in your mid rift and could result in a long trip to the toilet