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A Mumfiac is a person who is completely crazy about Mumford & Sons.
To be a mumfiac you must love all 4 of the members of Mumford & Sons
and know a lot about them!
pronounced Mumfy-ac
person1: "Have you heard of Mumford & Sons?"
person2: "Oh my gawd yes! They are so amazing! I'm a Mumfiac"
by mumfiac#1 July 02, 2011