12.2.10

coccyx

Raj: Okay, just to be clear, rollerskating was my idea and I’m very unhappy that you turned it into a double date and I hope you both fall on your asses and break your coccyxes.

Sheldon: The plural of coccyx is coccyges.

The Big Bang Theory, S03E14
(sólo para entendidos =P)