A person who is not circumcised, or just not cool at all. If you are a no top you are a loser. Anyone you hate can be considered a no top. No tops like to be extremely annoying and tend to be haters. No tops can range from those who have skateboards and say bro, to those who play guitar hero and study Calculus.
bill: Are you gonna give that kid a call back?
bob: No man he's a fucking no top!
Dave: you gonna eat that cabbage.
Karl: No dude only no tops eat cabbage...you fucking no top!