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1. Any of numerous solitary or colonial hydrozoans having a polyp rather than a medusa as the dominant stage of the life cycle.
2. The asexual polyp in the life cycle of a hydrozoan.

hy′droid′ adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. (Animals) of or relating to the Hydroida, an order of colonial hydrozoan coelenterates that have the polyp phase dominant
2. (Zoology) (of coelenterate colonies or individuals) having or consisting of hydra-like polyps
(Zoology) a hydroid colony or individual
[C19: from hydra + -oid]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈhaɪ drɔɪd)

1. of or pertaining to the hydrozoan order Hydroidea, including hydras and marine colonial forms.
2. the phase of hydrozoan development that consists of polyp forms.
[1860–65; hydr(a) + -oid; compare New Latin Hydroidea]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.hydroid - colonial coelenterates having the polyp phase dominanthydroid - colonial coelenterates having the polyp phase dominant
cnidarian, coelenterate - radially symmetrical animals having saclike bodies with only one opening and tentacles with stinging structures; they occur in polyp and medusa forms
planula - the flat ciliated free-swimming larva of hydrozoan coelenterates
class Hydrozoa, Hydrozoa - coelenterates typically having alternation of generations; hydroid phase is usually colonial giving rise to the medusoid phase by budding: hydras and jellyfishes
hydra - small tubular solitary freshwater hydrozoan polyp
siphonophore - a floating or swimming oceanic colony of polyps often transparent or showily colored
sertularian - feathery colony of long-branched stems bearing stalkless paired polyps
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
Larval chemical defenses against fishes occurred in each of the three sponges (Callyspongia, Calyx, and Ectyoplasia), one bryozoan (Bugula), and one hydroid (Eudendrium) that we chemically examined [ILLUSTRATION FOR FIGURE 8 OMITTED].
While heavy scouring, accompanying increased discharge, did not detrimentally affect insect taxa, it did affect hydroid population in two ways.
Since the largest hydroid colonies have the best chance of survival, sacrificing individuality can be a smart move.
Phylum Cnidaria Class Hydrozoa Order Anthoathecata Family Hydractiniidae Schuchertinia milleri (Torrey, 1902)--hedgehog hydroid (Fig.
This beautiful morphology, coupled with its rhythmic flexions propelling it through the water (Goodheart et al., 2015), has earned this species the nickname "Spanish shawl." Feeding preferentially on the cnidarian hydroid Eudendrium ramosum (McBeth, 1972), F.
Settlement of scallop, Pecten maximus, spat on natural substrates off south west England: the hydroid connection.
longissima); however, the medusae of this genus are all very similar in morphology, such that connection with their hydroid stage is almost impossible and often unreliable.
While there are scores of different military and civilian unmanned craft, Gibson's training efforts are focused on Hydroid and Bluefin vehicles.
NORDIC BUSINESS REPORT-16 June 2008-Norwegian high-tech group Kongsberg Gruppen ASA completes acquisition of US company Hydroid LLC(C)1994-2008 M2 COMMUNICATIONS LTD http://www.m2.com
Conversely Hydroid, an American company specialising in AUVs, was celebrating the decision of the Royal Navy to order two of its Remus 600 vehicles to meet the British force's need for an underwater reconnaissance drone.
These zones were characterized by a mussel-dominated assemblage at [approximately] 3 m; a hydroid and bryozoan dominated assemblage at [approximately] 5 m; a sponge, bryozoan, and ascidian dominated assemblage at [approximately] 10 m; and a deeper assemblage of sponges, bryozoans, brachiopods, and ascidians at [approximately] 18 m depth (Witman and Grange 1998).