Noun. A Gbff is your best friend forever on gchat. Usually used in a sarcastic method.
Dude, I was totally picked up by a gstalker. Now, all he does is gchat me all day. He thinks he is like my gbff or something. If he only knew I have a real boyfriend.
Gay Best Friend Forever
You know there is always a straight woman, and a gay man who are really good friends.
eg. Will and Grace... Will is her GBFF