• WordNet 3.6
    • n Cnidaria hydras; polyps; jellyfishes; sea anemones; corals
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Webster's Revised Unabridged Dictionary
    • n. pl Cnidaria nĭ*dā"rĭ*ȧ (Zoöl) A comprehensive group equivalent to the true Cœlenterata, i. e., exclusive of the sponges. They are so named from presence of stinging cells (cnidae) in the tissues. See Coelenterata.
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Century Dictionary and Cyclopedia
    • cnidaria Those Cœlentera which have thread-cells or cnidœ; the Cœlenterata, with the exception of the sponges. See Cœlentera.
    • ***


Webster's Revised Unabridged Dictionary
NL. See Cnida


In literature:

Next in order come the tentacles, common to all Cnidaria.
"Encyclopaedia Britannica, 11th Edition, Volume 14, Slice 2" by Various