A hetrosexual man or woman that is subconiously scared they will become gay.
'phobic' = scared.
Rob: I am gay. *hugs John*
Harry: You're both fags.
Jess: :O! Harry! You are homophobic!
Harry: Am I?! What does that mean?!
Jess: It means you're scared that Rob or John might start hitting on you.
Rob:But we love each other! Not Harry!
John: *shifty eyes*