Pygidium
/pɪˈdʒɪdiəm/noun
The terminal or posterior body region of certain arthropods, annelids, and other invertebrates.
Did you know?Pygidium comes from Ancient Greek *pygē*, “buttock” or “rump,” a root preserved in scientific terms describing posterior anatomy.
Etymological Timeline
Ancient Greek
Greek
pygē (πυγή)
“Buttock, rump, or buttocks”
Ancient Greek
Greek
pygidion (πυγίδιον)
“Little rump or small posterior part; a diminutive form of *pygē*”
19th Century
New Latin
pygidium
“A terminal or posterior body region in zoological classification”
19th Century
Scientific English
pygidium
“The terminal division of the body, especially in trilobites and various arthropods”
Modern English
English
pygidium
“The rear body region of certain invertebrates, often bearing the anus or terminal structures”
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