A word to describe someone who is very stupid. Must only be used after someone says/does something that is unbelievably, astonishingly, incredibly stupid.
Comes from FOX news political commentator Bill O'Reilly who may be the most stupid person on earth. Is sure to win a Darwin Award when he dies.
"Tide goes in, tide goes out. You CAN'T explain that!"
"Dude you are a total O'Reilly"
"I just had sex without a condom and got the girl pregnant and I have an STD"
"You fucking O'Reilly"