prostomium

noun

pro·​sto·​mi·​um prō-ˈstō-mē-əm How to pronounce prostomium (audio)
plural prostomia prō-ˈstō-mē-ə How to pronounce prostomium (audio)
: the portion of the head of an annelid worm (such as an earthworm) that is situated in front of the mouth
prostomial adjective

Word History

Etymology

New Latin, from Greek pro- + stoma mouth — more at stomach entry 1

First Known Use

1870, in the meaning defined above

Time Traveler
The first known use of prostomium was in 1870

Dictionary Entries Near prostomium

Cite this Entry

“Prostomium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/prostomium. Accessed 31 Oct. 2024.

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