1. Belonging to an exclusive group (clique
) made up of people wearing Dr Scholls Gel inserts.
2. Having greater perceived social value due to inclusion in, or relation to, said group.
This term is often used in conjunction with other words that rhyme with it. The more rhyming words used, the more one is Gellin'. Misguided individuals who believe that they are Gellin' when they are not often say that they are "gelling." It is easy to pick out these individuals because they never rhyme their words. And they are horrible dancers.