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plural noun

: an order of Hydrozoa comprising forms alternating a well-developed asexual polyp generation with a generation of free medusae or of abortive medusoid reproductive structures on the polyps see leptomedusae


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taxonomic synonym of hydrozoa

Word History


Plural noun

New Latin, from Hydra, included genus + -oida

New Latin, from Hydra, included genus + -oida

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Dictionary Entries Near Hydroida

Cite this Entry

“Hydroida.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Hydroida. Accessed 19 Apr. 2024.

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