This shows grade level based on the word's complexity.
protostome
[ proh-tuh-stohm ]
/ ËproÊ tÉËstoÊm /
See the most commonly confused word associated with protostome
Save This Word!
This shows grade level based on the word's complexity.
noun Zoology.
any member of the lower invertebrate phyla in which the mouth appears before the anus during development, cleavage is spiral and determinate, and the coelom forms as a splitting of the mesoderm.
COMPARE MEANINGS
Click for a side-by-side comparison of meanings. Use the word comparison feature to learn the differences between similar and commonly confused words.
QUIZ
WILL YOU SAIL OR STUMBLE ON THESE GRAMMAR QUESTIONS?
Smoothly step over to these common grammar mistakes that trip many people up. Good luck!
Question 1 of 7
Fill in the blank: I canât figure out _____ gave me this gift.
Compare deuterostome.
Words nearby protostome
protoporphyrin, protopresbyter, Protosemitic, protostar, protostele, protostome, Proto team, prototherian, prototroph, prototrophic, prototype
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Scientific definitions for protostome
protostome
[ prÅtâ²tÉ-stÅmâ² ]
Any of a major group of animals defined by its embryonic development, in which the first opening in the embryo becomes the mouth. At this stage of development, the later specialization of any given embryonic cell has already been determined. Protostomes are one of the two groups of animals having a true body cavity (coelom) and are believed to share a common ancestor. They include the mollusks, annelids, and arthropods. Compare deuterostome.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.