A very narrow-minded person. Bigots can come from a variety of backgrounds. Their level of formal education can range from none at all to perpetual student. They may or may not be affiliated with a religion. One thing bigots share is an undying devotion to their own ideologies and assumptions.
snoopdrj: "The South is full of bigoted and racist people. Anyone who doesn't agree with me is wrong."
stan: "Why do you believe that, snoop?"
snoopdrj: "I've met racist people while living here, which means racism permeates the South."
stan: "I wouldn't say that. Sure, there are some areas which are more racist than others, but you'll find that anywhere."
snoopdrj: "Are you fucking retarded? You're delusional! You've obviously lived a very sheltered life."