Juju-flop

Juju-flop is a profanity with no direct analog in American English slang. It seems to refer to the act of sexual intercourse, excrement, or both.

It was first used in the BBC Radio Series, "The Hitchhiker's Guide To the Galaxy, Secondary Phase, " as part of the Guide entry on Belgium.

Juju-flop  appears to carry a meaning and emotional connotation somewhere between the American slang, "fuck " and "shit."