O / orthŏpȳgĭum
noun greek

orthŏpȳgĭum

gen. orthŏpȳgĭi · gender neuter · decl. 2nd
= ὀρθοπύγιον
the rump and tail feathers of birds
the rump and tail feathers of birds, Mart. 3, 93, 12 (al. orrhopygium = ὀρροπύγιον, of the same meaning).