Often heard in movies where the characters are Italian Americans living in New York.
It simply means that you don't believe what someone else said.
Henry Hill: There it is, you see that Mike? You see that Helicopter? See it right there, right infront of us there? I think it's been following me all morning.
Mikey: Get the fuck outta here! What are you, nuts?
Buy a
Get the fuck outta here!
mug!