Hydroid may refer to:
Biology
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Hydroid (botany)
A hydroid is a type of vascular cell that occurs in certain bryophytes. In some mosses such as members of the Polytrichaceae family, hydroids form the innermost layer of cells in the stem. At maturity they are long, colourless, thin walled cells ...
, a type of vascular cell that occurs in certain bryophytes
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Hydroid (zoology)
Hydroids are a life stage for most animals of the class Hydrozoa, small predators related to jellyfish.
Some hydroids such as the freshwater '' Hydra'' are solitary, with the polyp attached directly to the substrate. When these produce buds ...
, a life stage for most animals of the class Hydrozoa
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Garveia'', a genus of cnidarians, including:
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Garveia annulata'', the orange hydroid
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Garveia arborea'', the orange or hedgehog hydroid
Business
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Hydroid Inc., an autonomous underwater vehicle manufacturer
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