Protostomia

plural noun
Pro·​to·​sto·​mia

Definition of Protostomia

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

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History and Etymology for Protostomia

New Latin, from prot- + -stomia

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Cite this Entry

“Protostomia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Protostomia. Accessed 26 May. 2020.

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