jumbo/LARGE
From Homestar Runner Wiki
jumbo/LARGE is an inside joke that Strong Bad made up in road trip. According to him, "every good road trip needs an inside joke," so he made up jumbo/LARGE. He also calls it a maxymoron, in contrast to an oxymoron (a phrase which is self-contradictory). From the context, we infer that a maxymoron is a phrase which places emphasis on itself.