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1.
1. A term used to express ones up most excitement when hearing good news; also a form of agreement.
2. A term used to express extreme pwnage
3. When shit goes down and you are the victor

Boom-Yup is closely related to fuck-yeah, ace, wicked, and Damn-straight, and in some cases, get owned(see definition 2)
1. Person A: Dude, i just realized i have no friday classes ever we partying every day. Person B: BOOM-YUP!
1b. Person A: yo i just got some dank weed, lets go toke. Person B: Boom-yup.
2. Damn I just had a 12 kill streak with 6 headshots. Boom-Yup!
3. Person A: I WILL FUCK YOU UP! Person B (after beating person a): Boom-Yup
by JaFool13 September 13, 2009