being in a situation when you have diarrhea.
do you want to come down the pub or are you still being bum sick?
When you sit down to pee and the urination secretes into your anus all the way.
dude, guess what?! I sat down to take a piss and had a peepee bum!
When you poo and it exits your colon at over 30MPH
Guy1: I just went into the bathroom to take a large poo, and rather than having a normal bowel movement it removed itself from my ass so fast that it ripped my ring!
Guy2: Dude! you just bum rocketed!
A person that decides that it is necassary to hang around a train station. These people are often poor and Smoke Ciggarrettes. Due to their poorness they will hastle bystanders for a Cigarrette and/or "2 Bucks".
"Hey mate can i have a 2 bucks and a cigarrette."
"Get a job you stupid station bum"
A rather naughty form of tickling.
Indeed there is an entire world of bum bum just waiting to be tickled.
I don't however condone tickling anyones bum bum.
Edward likes to tickle his fair share of bum bums.
That fact alone should un-invite you to start bum tickling.
The chourus part of the song "Disturbia" by Rihanna; one of the lamest songs ever written.
Gay Guy: Hey have you heard Rhihanna's new song?
Jim: No, which one?
Gay Guy: It goes like "Bum Bum Bee Da bum bum bee dum dum... Disturbia!"
Jim: Omg thats horrible, please stop before I go deaf!
Also known as a wedgie, where the underpants are drawn/forced/pulled/slipped up into the butt crack.
That hungry bum they gave Clarence in gym class left a big skid mark on his gauchies.