pygidium

noun

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
pī-ˈji-dē-əl How to pronounce pygidium (audio)
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

Rhymes for pygidium

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Browse Nearby Words

Pygidiidae
pygidium
pygmaean
See all Nearby Words

Cite this Entry

“Pygidium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pygidium. Accessed 7 Jul. 2026.

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