py·​gid·​i·​um pī-ˈji-dē-əm How to pronounce pygidium (audio)
plural pygidia pī-ˈji-dē-ə How to pronounce pygidium (audio)
: a caudal structure or the terminal body region of various invertebrates
pygidial adjective

Example Sentences

Recent Examples on the Web The trilobite spans 146 meters from cephalon to pygidium, or head to tail, and is carved into the shape of a spiny Ceraurus trilobite instead of the plainer state fossil, Calymene. Giorgia Guglielmi, Science | AAAS, 22 Sep. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'pygidium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History


New Latin, from Greek pygidion, diminutive of pygē rump

First Known Use

1848, in the meaning defined above

Time Traveler
The first known use of pygidium was in 1848

Dictionary Entries Near pygidium

Cite this Entry

“Pygidium.” Dictionary, Merriam-Webster, Accessed 5 Feb. 2023.

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