This is a nick-name you use when you are online. Choosing a handle is hard, and should be done carefully. Everyone has seen Top Gun. A dweeb is someone new to Air Warrior. Everyone started out as a dweeb.
Some people remain dweebs for the rest of their natural life.
Others leave dweeb-hood behind. Everyone does dweebish things every now and then. Like, get into a turn fight with a Zero. Basically, a bomber.