THE. WEIRDEST. NAME. AVAILABLE
I'm not joking or anything, this is a real definition. The word bthero usually used for people that ran out of idea, or simply they just didn't have a good naming sense.
It is uncertain whether this is a slang or not, but his word is somewhat popular in east asian teenagers, usually they use this word to describe something that they didn't know about.
Dude1: Hey, do you know the formula of gravity and mass?