[proh-stoh-mee-uh m]

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

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

Origin of prostomium

1865–70; < New Latin < Greek prostómion mouth. See pro-2, stoma, -ium
Related formspro·sto·mi·al, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for prostomium

Historical Examples of prostomium

British Dictionary definitions for prostomium


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

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

Online Etymology Dictionary, © 2010 Douglas Harper