1.) v. a phrase meaning "i concur"
2.) v. to smoke (youp) cannabis 3.) v. can substitute any verb
1.) "hey joe, you want to order a pizza?" joe:"Bet that youp."
2.) "hey i got some dank-dank, lets go bet that youp!"
3.) "ill be over as soon as i bet that youp on class"
It originated in 2000 around South Gwinnett in Georgia and it means "Definitely" or "Im excited" or "I can't wait"or "For sure" or "Cool beans" or "Im down" or "Im game" or "I will be there" or "Yes" or as an updated version of saying "You bet" or "You betcha" which means you agree and are looking forward to an upcoming event/plans of some sort.
Dude: Are you coming to the club tomorrow night? They said Usher is performing and there will be hella chicks there"
Dude 2: Fuck yeah bet that up!