GBT refers to the size of a bitchy girls boob. Hence they are so small they could be golf balls. The word can also describe the following:
GBT otherwise known as Golf Ball Tits refer to a young and wide spread group of slutty woman who cannot yet even think of having children. Yet they dress like they are hookers and do not act much better. They are adolescent wanna-bee sexkitten
s with no boobs. They usually steal the crown from the more eligible Queen Bee
. People look at them as vessels of beauty when really they are prostitots
. It usually effects 6th-8th graders yet some sad examples can be found among 9th graders.