from Wiktionary, Creative Commons Attribution/Share-Alike License
- proper n. A taxonomic class within the phylum Cnidaria — the hydrozoas.
from the GNU version of the Collaborative International Dictionary of English
- n.pl. The Acalephæ; one of the classes of cœlenterates, including the Hydroidea, Discophora, and Siphonophora.
from The Century Dictionary and Cyclopedia
- A class of Cœlenterata, one of two prime divisions of that subkingdom, Actinozoa being the other.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. coelenterates typically having alternation of generations; hydroid phase is usually colonial giving rise to the medusoid phase by budding: hydras and jellyfishes
Ancient Greek ὕδωρ, water + ζῷον, animal (Wiktionary)