hydroid

American  

[hahy-droid] / ˈhaɪ drɔɪd /

adjective

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

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noun

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

hydroid British  

/ 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

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noun

1. a hydroid colony or individual

hydroid Scientific  

/ 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.

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Etymology

Origin of hydroid

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

Example Sentences

An example is the colonial hydroid called an Obelia. The sessile polyp form has, in fact, two types of polyps, shown in Figure 3.

From Textbooks • Jan. 1, 2015

But because there are so few hydroid experts, our understanding of these species is staggeringly incomplete.

From New York Times • Nov. 28, 2012

There are significantly more crab experts, for instance, than hydroid experts.

From New York Times • Nov. 28, 2012

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

From New York Times • Nov. 28, 2012

If the stem of this hydroid, which is usually covered with polyps, is put into an aquarium the polyps soon fall off.

From Darwin and Modern Science by Seward, A. C. (Albert Charles)

Related Words

• tumor