The single greatest word ever uttered into the universe.
Meaning a male human usually of caucasian decent that is both a homosexual and enjoys cocks very much. He enjoys them in his mouth his butthole, nose, or possibly other holes depending on the seriousness of his homosexual sexual intercourse. Cockfags are usually the most antic fags and they jump even more than regular fags for cock.
So, they are extremely cocky for cocks.
Timmy's a cockfag, he put Timmy's cock in his ear!