Joseph Xu means in slang: He’s a complete dumbass. He is also the most nerdy dude that I’ve ever seen in my entire life. Although he tries hard to be a MLB player some people don’t think so. Joseph brags all the time about Ethan Kim being his friend. I wouldn’t stop extolling how good you are at 2k if I was you. (in Slang Dictionary, added by Odón Arias)