Etymology: Play on the famously abstruse novel Foucault's Pendulum by Umberto Eco and its title's source, Jean Bernard Leon Foucault's pendulum, a simple pendulum suspended from a long wire and set into motion along a meridian. The plane of motion appears to turn clockwise in the Northern Hemisphere and counterclockwise in the Southern Hemisphere, demonstrating the axial rotation of the earth.
1. the moment of not knowing if poops are dangling or not after a sphincter-numbing bowl movement 2. confusion when the whirl of toilet flush snatches a still-dangling poop from one's anal. See also: defecult.
(BOB EXITS THE BATHROOM)
Sally: How'd it go in there? Defecult?
Bob: God, no. It was even worse this time... more like Defecult's Pendulum.