The Collaborative International Dictionary
Pygal
Pygal \Py"gal\, a. [Gr. ? the rump.] (Anat.) Situated in the region of the rump, or posterior end of the backbone; -- applied especially to the posterior median plates in the carapace of chelonians.
Wiktionary
pygal
a. (context anatomy English) Situated in the region of the rump, or posterior end of the backbone; applied especially to the posterior median plates in the carapace of chelonians.