plural noun Pro·to·sto·mia

Definition of Protostomia

  1. :  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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Origin and Etymology of protostomia

New Latin, from prot- + -stomia

Seen and Heard

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a brief usually trivial fact

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