from The American Heritage® Dictionary of the English Language, 4th Edition
- n. An echinoderm of the class Echinoidea, which includes the sand dollars and sea urchins.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Any sea urchin or sea dollar of the class Echinoidea
from the GNU version of the Collaborative International Dictionary of English
- adj. Of or pertaining to the Echinoidea.
from The Century Dictionary and Cyclopedia
- Having the form or appearance of a sea-urchin: in entomology, applied to certain insect-eggs which are shaped like an echinus, and covered with crowded deep pits.
- Pertaining to the Echinoidea.
- n. In zoology, one of the Echinoidea.
Sorry, no etymologies found.
An unidentified holothurian is common on the northern reef flats, and an echinoid Heterocentrotus sp. (possibly H. trigonarius) is locally abundant on the sloping marginal reefs and shallow reef flat of the northern beach.
Minokawa T, Amemiya S (1999) Timing of the potential of micromere-descendants in echinoid embryos to induce endoderm differentiation of mesomere-descendants.
Gao F, Davidson EH (2008) Transfer of a large gene regulatory apparatus to a new developmental address in echinoid evolution.