Bis is something you put whatever you’re claiming or saying on. It’s a way of swearing something being said is true. If the user of bis is lying then they are eligible for a punishment of slaps. You do not lie on bis.
Origin:
The word bis is short for bismilah which is an Arabic way of of saying “in the name of god” similar to when people say “on god” when they swear something.
-“Grb said we could have a sesh at his”
-“Say bis” or “bis?”
-“bis bro”