A term used ironically to describe anything decidedly less than wonderful. Originally from the movie "Shaun of the Dead". Sometimes spelt fuckadoodledoo.
"I went to McDonald's and got a freeBig Mac"
"Well, fuckadoodledo..."
ex: when working on a project and everything has gone wrong when you are about to give up everything something works out of nowhere..the moment of happiness is expressed by screaming fuckadoodle