hydroid

1 of 2

adjective

hy·​droid ˈhī-ˌdrȯid How to pronounce hydroid (audio)
: of or relating to a hydrozoan
especially : resembling a typical hydra

hydroid

2 of 2

noun

: hydrozoan
especially : a hydrozoan polyp as distinguished from a hydrozoan medusa

Examples of hydroid in a Sentence

Recent Examples on the Web
Adjective
Scientists are divided over whether a creature sitting near the wheel — which resembles an ostrich feather crossed with a Christmas tree — is a hydroid or a black coral. New York Times, 11 Mar. 2022 Coastal podded hydroid Aglaophenia pluma, open-ocean Planes crab and open-ocean Lepas gooseneck barnacles colonize a piece of floating debris. NBC News, 3 Dec. 2021
Noun
Polyps are part of the life cycle of jellyfish and the related group of animals known as hydroids. Aspen Pflughoeft, Miami Herald, 20 Feb. 2024 Common coastal stowaways included amphipods, isopods, hydroids and bryozoans, most of which originated from the northwest Pacific. Tim Brinkhof, Discover Magazine, 25 Nov. 2023 The rock was also lined with wispy filaments, perhaps a component of the bacterial mats, or perhaps a peculiar animal known as a hydroid. Matt Simon, Wired, 15 Feb. 2021 Some grow algae and hydroid gardens on their backs, others can change color at will, and one, the decoy scorpionfish, has a lure on its dorsal fin that resembles a tiny, swimming fish. Troy Farah, Smithsonian, 29 Mar. 2018 The nudibranch, besides using the hydroids for habitat, regularly consume its home colony’s polyps. Sid Perkins, Science | AAAS, 31 Oct. 2017 In the wild, these slugs are known to feed on hydroids, an invertebrate marine organism. Brigit Katz, Smithsonian, 4 Nov. 2017 Fourteen of the slugs made a beeline for the hydroid that had been fed, according to a study published recently in Biology Letters. Brigit Katz, Smithsonian, 4 Nov. 2017 In shallow waters of the Mediterranean and along the Atlantic coast of western Africa, C. peregrina lives on and near corallike colonies of polyps called hydroids. Sid Perkins, Science | AAAS, 31 Oct. 2017

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'hydroid.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Adjective

ultimately from New Latin Hydra

First Known Use

Adjective

circa 1864, in the meaning defined above

Noun

1865, in the meaning defined above

Time Traveler
The first known use of hydroid was circa 1864

Dictionary Entries Near hydroid

Cite this Entry

“Hydroid.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydroid. Accessed 18 Apr. 2024.

Kids Definition

hydroid

1 of 2 adjective
hy·​droid ˈhī-ˌdrȯid How to pronounce hydroid (audio)
: of or relating to the hydrozoans
especially : resembling a hydra

hydroid

2 of 2 noun
: hydrozoan
especially : a hydrozoan polyp in contrast to a hydrozoan jellyfish

Medical Definition

hydroid

1 of 2 adjective
hy·​droid ˈhī-ˌdrȯid How to pronounce hydroid (audio)
: of or relating to a hydrozoan
especially : resembling a typical hydra

hydroid

2 of 2 noun
: hydrozoan
especially : a hydrozoan polyp as distinguished from a medusa

More from Merriam-Webster on hydroid

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!