hy·​dro·​zo·​an | \ ˌhī-drə-ˈzō-ən How to pronounce hydrozoan (audio) \

Definition of hydrozoan

: any of a class (Hydrozoa) of cnidarians (such as the hydra, fire coral, and Portuguese man-of-war) that includes solitary and colonial polyps and medusae but often having the medusa stage reduced or absent and lacking nematocysts in the digestive cavity — see siphonophore

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Other Words from hydrozoan

hydrozoan adjective

Examples of hydrozoan in a Sentence

Recent Examples on the Web The creatures, which are marine hydrozoans and relatives of jellyfish, have recently been spotted on Sullivan’s Island and in Hilton Head. USA TODAY, "Black Hills yaks, serious senioritis on campus, Pony Express: News from around our 50 states," 10 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'hydrozoan.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of hydrozoan

1877, in the meaning defined above

History and Etymology for hydrozoan

ultimately from Greek hydr- + zōion animal — more at zo-

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Time Traveler for hydrozoan

Time Traveler

The first known use of hydrozoan was in 1877

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Cite this Entry

“Hydrozoan.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/hydrozoan. Accessed 17 January 2020.

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More Definitions for hydrozoan


hy·​dro·​zo·​an | \ -ˈzō-ən How to pronounce hydrozoan (audio) \

Medical Definition of hydrozoan

: any of the class Hydrozoa of coelenterates

Other Words from hydrozoan

hydrozoan adjective

Comments on hydrozoan

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a plan in which a last survivor takes all

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