prostomium

[ proh-stoh-mee-uh m ]

/ proʊˈstoʊ mi əm /

noun, plural pro·sto·mi·a [proh-stoh-mee-uh] /proʊˈstoʊ mi ə/.

the unsegmented, preoral portion of the head of certain lower invertebrates.

Nearby words

Origin of prostomium

1865–70; < New Latin < Greek prostómion mouth. See pro-², stoma, -ium

Related formspro·sto·mi·al, adjective

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for prostomium

Prostomium: The region in front of the mouth; the preoral part of the head.
The Sea-beach at Ebb-tide|Augusta Foote Arnold
Prostomium wider than long, deeply bilobed, the median tentacle inserted deeply in the intervening incision.
Journal of Entomology and Zoology, Vol. 11. No. 1.|Various
Prostomium of usual general form; consisting of fourteen or fifteen rings.
Journal of Entomology and Zoology, Vol. 11. No. 1.|Various
Prostomium with a lateral process or horn on each side in front, notched in front at middle.
Journal of Entomology and Zoology, Vol. 11. No. 1.|Various

Prostomium generally small, sometimes prolonged, but never bearing tentacles or processes.
Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 7|Various

British Dictionary definitions for prostomium

prostomium

/ (prəʊˈstəʊmɪəm) /

noun plural -mia (-mɪə)

the lobe at the head end of earthworms and other annelids: bears tentacles, palps, etc, or forms part of a sucker or proboscis

Derived Formsprostomial, adjective

Word Origin for prostomium

via New Latin from Greek prostomion mouth

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for prostomium

prostomium

1870, Latinized form of Greek prostomion "fore-mouth, something before the mouth," from pro "before" (see pro-) + stoma "mouth" (see stoma).