1. Nub is worse than a noob. A nub is someone whose been doing something for a while and is still slow and/or a retard at doing that thing.
2. Nub is someone not on your level but thinks they are so awesome when they are not.
1: OMG alexa is such a nub...she keeps taking my words when i clearly tell her its mine. I own NUB and every variation of it.
2:Dude i swear josh is a nub. he think he owns at halo when he completely fails at it.