echinoderm

noun

1. An animal of the phylum Echinodermata, comprising radially symmetric, spiny-skinned marine animals including seastars, sea urchins, sea cucumbers, crinoids, and sand dollars.

   “Comparatively few additions were therefore made to the previously known Echinoderm-fauna of Brazil, only a single species, a Leptasterias, being with certainty new to science.”

   “Many echinoderms are still bilateral as larvae, and swim freely in the ocean like baby fish.”