One who generally has either no knowledge of, or regard for, basic social etiquette (e.g. saying hello before attempting to initiate a conversation); a person you would want to go away. Said individual typically alternates between unsociable and too sociable.
NOTE: The average adult will have between 75 and 80 "spaz" roommates during the course of their miserable lifetime.
(The National Science Foundation)
Spaz: "Is this your dog? I hate dogs. So then she said I spend waaayy too much timeplaying videogames and jerking off. I'm pretty sure you clogged the toilet; I just took a huge shit in it. I'm BORED. Bye." *slams door*
Yet another name for Vagina, also known as Spaz Hole. Comes from the idea that when the clitoris is stimulated the woman can sometimes move involuntary like a disabled person (spastic) would when they have a fit. This "spaz" motion is referred to in the name.