mesozoan

[mez-uh-zoh-uh n, mes-, mee-zuh-, -suh-]Zoology
adjective
  1. of or relating to the mesozoans.

Origin of mesozoan

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

mesozoan in Science

mesozoan

[mĕz′ə-zōən]
  1. Any of a variety of very small parasitic marine animals of the group Mesozoa. Mesozoans resemble worms and have simple bodies divided into two layers. The outer layer is covered with cilia, and there are no internal organs. The taxonomic status of the Mesozoa is unclear, as some scientists believe the mesozoans to be an ancient and primitive group and others regard them as degenerate forms of more complex animals.
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