What is "uropygium"

Uropygium \U`ro*pyg"i*um\, n. [NL., fr. Gr. ?, (corrupted form) ?; ? the end of the os sacrum + ? rump.] (Anat.) The prominence at the posterior extremity of a bird's body, which supports the feathers of the tail; the rump; -- sometimes called pope's nose.

n. The posterior part of a bird's body from which the tailfeathers grow.

n. posterior part of a bird's body from which the tail feathers grow