plural noun

: animals in which the definitive mouth develops directly from the blastopore (as most worms, bryozoans, brachiopods, mollusks, and arthropods) compare deuterostomia

Word History


New Latin, from prot- + -stomia

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Dictionary Entries Near Protostomia

Cite this Entry

“Protostomia.” Dictionary, Merriam-Webster, Accessed 11 Dec. 2023.

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