diatom

noun
di·​a·​tom | \ ˈdī-ə-ˌtäm How to pronounce diatom (audio) \

Definition of diatom

: any of a class (Bacillariophyceae) of minute planktonic unicellular or colonial algae with silicified skeletons that form diatomaceous earth

Examples of diatom in a Sentence

Recent Examples on the Web Brackish diatoms indicate lower lake levels because the water becomes saltier as the water evaporates. Emily J. Beverly, Quartz Africa, "In 100,000 years Lake Victoria has dried up three times—it could happen again," 26 Jan. 2020 In roughly a third of the ocean, iron is so rare that its absence can hinder the growth of diatoms and other phytoplankton. Emily Underwood, Smithsonian Magazine, "The Complicated Role of Iron in Ocean Health and Climate Change," 6 Jan. 2020 From diatoms encased in glass to dinoflagellates that can cause toxic algae blooms, phytoplankton are a diverse group of algae that live in the ocean. Stephanie De Marco, Los Angeles Times, "Ocean robots take the pulse of our planet by measuring microbes," 18 Sep. 2019 At least three species of dinoflagellates and one diatom species are responsible for the toxic mess of red tides in the United States. Jenny Howard, National Geographic, "Red tides, explained," 5 July 2019 The Pseudonitzchia species of algae, forms of diatoms, more commonly create red tides off the coast of California. Jenny Howard, National Geographic, "Red tides, explained," 5 July 2019 Paleosols are typically full of pollen and microfossils of simple organisms, such as diatoms, a kind of algae that can indicate climate conditions. Gemma Tarlach, Discover Magazine, "Rising Seas Swallowed Countless Archaeological Sites. Scientists Want Them Back," 20 May 2019 Diatomaceous earth is an organic powder that consists of the fossilized remains of tiny aquatic organisms, called diatoms. Joseph Truini, Popular Mechanics, "How to Get Rid of Termites," 8 Jan. 2019 Sprinkle Diatomaceous Earth Diatomaceous Earth, or DE, is a white crumbly powder consisting of the fossilized remains of diatoms, a class of algae. Rebecca Straus, Good Housekeeping, "5 Ways to Get Rid of Silverfish," 25 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'diatom.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of diatom

1845, in the meaning defined above

History and Etymology for diatom

ultimately from Greek diatomos cut in half, from diatemnein to cut through, from dia- + temnein to cut — more at tome

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Time Traveler for diatom

Time Traveler

The first known use of diatom was in 1845

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Statistics for diatom

Last Updated

10 Feb 2020

Cite this Entry

“Diatom.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diatom. Accessed 25 Feb. 2020.

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More Definitions for diatom

diatom

noun
di·​a·​tom | \ ˈdī-ə-ˌtäm How to pronounce diatom (audio) \

Medical Definition of diatom

: any of a class (Bacillariophyceae) of minute planktonic unicellular or colonial algae with silicified skeletons that form diatomite

More from Merriam-Webster on diatom

Rhyming Dictionary: Words that rhyme with diatom

Britannica.com: Encyclopedia article about diatom

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