hydroid

[ hahy-droid ]

adjective

1. noting or pertaining to that form of hydrozoan that is asexual and grows into branching colonies by budding.

noun

1. the phase of a hydrozoan coelenterate that consists of polyp forms usually growing as an attached colony.

hydroid

/ ˈhaɪdrɔɪd /

adjective

1. of or relating to the Hydroida, an order of colonial hydrozoan coelenterates that have the polyp phase dominant
2. (of coelenterate colonies or individuals) having or consisting of hydra-like polyps

noun

1. a hydroid colony or individual

hydroid

/ hī′droid′ /

1. Any of numerous, usually colonial marine cnidarians, having a polyp rather than a medusoid form as the dominant stage of the life cycle. Hydroids have a simple cylindrical body with a mouthlike opening surrounded by tentacles. Most species form colonies with individual hydroids branching off from a common hollow tube that is probably used to share ingested food. The young develop from eggs or from buds. The most well-known hydroids are the hydras (genus Hydra ), which are atypical in being both freshwater and solitary.

Word History and Origins

Origin of hydroid¹

First recorded in 1860–65; hydr(a) + -oid

Word History and Origins

Origin of hydroid¹

C19: from hydra + -oid

Example Sentences

To test whether Cratena nudibranchs had a penchant for hydroids that had freshly eaten, the authors did lab experiments on 25 slugs, presenting each with four mesh bags.

From Seattle Times

The nudibranch, besides using the hydroids for habitat, regularly consume its home colony’s polyps.

From Science Magazine

Cardinalfish zip by a loggerhead turtle as it rests among feathery invertebrates called hydroids.

From National Geographic

In other hydroid species, the medusa dies after it spawns.

From New York Times

The species can grow up to 3.2 cm long, and can be found among all kinds of algae, sea grass, sponges, hydroids, alcyonarians and tunicates all over the Northern Hemisphere.

From Scientific American

Related Words

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