(interj.) A phrase meaning fuck with distant ties to the flying fuck (the flying fuckfish is the primary source of food fot the flying fuck). Used if the situation you're cursing is bizarre, you're confused, or if you're in the mood for alliteration. Can also be used interchangeably with flying fuck.
Juwanna Tinkle: What's the capital of Assyria?!
Me: Flying fuckfish! How the hell should I know?