cnidarian

American  

[nahy-dair-ee-uhn] / naɪˈdɛər i ən /

noun

1. any invertebrate animal, as a hydra, jellyfish, sea anemone, or coral, considered as belonging to the phylum Cnidaria, characterized by the specialized stinging structures in the tentacles surrounding the mouth; a coelenterate.

---

adjective

1. belonging or pertaining to the Cnidaria.

cnidarian British  

/ knaɪ-, naɪˈdɛərɪən /

noun

1. any invertebrate of the phylum Cnidaria , which comprises the coelenterates

---

adjective

1. of, relating to, or belonging to the Cnidaria

cnidarian Scientific  

/ nī-dâr′ē-ən /

1. Any of various invertebrate animals of the phylum Cnidaria, having a body with radial symmetry and tentacles that bear microscopic stinging capsules called nematocysts. The tentacles surround a mouth that opens into a saclike internal cavity and that is used both for ingesting food and for eliminating wastes. Cnidarians evolved in the Precambrian Era, but it is not known from what type of organism. Cnidarians include the jellyfishes, hydras, sea anemones, and corals.

---

Etymology

Origin of cnidarian

Cnidari(a) + -an

Example Sentences

"The AO has a striking complexity when compared to apical organs of cnidarian and bilaterian. It is so unique!"

From Science Daily • Mar. 6, 2026

Scientists do not yet understand all cnidarian cell types, let alone their functions.

From Scientific American • Jul. 5, 2021

Your typical cnidarian does not, after all, appear to have much in common with a human being.

From New York Times • Nov. 28, 2012

The colony-forming cnidarian Gerardia was frequently identified outside the submersible.

From Science Magazine • Sep. 7, 2012

Charniodiscus, a frond with a disklike base, he classifies as a colonial cnidarian, the phylum that includes jellyfish, sea anemones and sea pens.

From Time Magazine Archive