What is Bum's Rush?
1.
Ejection from an area or establishment, classically via being picked up by the seat of your pants and the back of your shirt. The term has come to include most forms or violent rejection. Presumably this came from the ejecting of panhandlers from business establishments.
I went to a party, but I got too drunk and they gave me the bum's rush.
2.
The violent ejection of an obnoxious slob from a saloon. The bum's rush is performed by a bouncer.
You must NEVER say "bum's rush" in the presence of a white liberal. She will surely be offended! Instead, you must always say "Homeless Person's Manditory Egression." Then the white liberal won't be offended at all.
I was sitting in the No Name Bar in Sausalito, wearing an IDJ. With me were two young ladies wearing see-through tops. The bouncer ordered me to leave because I was wearing an offensive garment. I looked at my companions, then asked the bouncer, "Can I stay if I grow tits?" The bouncer gave me the bum's rush.
See
3.
diarrhea
A play on the "forceful ejection" meaning, instead implying that there is poop rushing from your bum (butt).
Employer: I'll give you the bum's rush!
Employee: Where I come from, we call that diarrhea.
All that fatty meat gave my the bum's rush!