A slang way of saying something is way beyong believable. Compare to Rifuccingdiculous or ridiculous or unimaginable. Kansas Governor had to pass a law to prevent cops from having sex at traffic stops.Unfuccingbelievable!!!
Definitions include: inside the military, slang for practice of taking a piece of intelligence or a request that should be pushed through the chain of command - checked at levels and sent from one level to another - and bringing it straight to the highest authority. -- The New Yorker