pygostyle: Meaning and Definition of

py•go•style

Pronunciation: (pī'gu-stīl"), [key]
— n. Ornith.
  1. the bone at the posterior end of the spinal column in birds, formed by the fusion of several caudal vertebrae.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.