pygidium

noun

py·gid·i·um pī-ˈji-dē-əm

plural pygidia pī-ˈji-dē-ə

: a caudal structure or the terminal body region of various invertebrates

pygidial

pī-ˈji-dē-əl

adjective

Word History

Etymology

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

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Browse Nearby Words

Pygidiidae

pygidium

pygmaean

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Cite this Entry

Style

“Pygidium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pygidium. Accessed 3 Nov. 2025.

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