A lie that is told for no conceivable reason. The lie itself is plausible but ultimately unproveable. It disappears as quickly as it is uttered under its own inconsequence.
Derives from the apocryphal tale that author Tom Clancy was unliked as a child and taunted with the nickname "Clancypants."
Origin: "Did you know that as a child they used to call him Clancypants?"