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 The algal cell pictured here in red, a Coscinodiscus diatom, is 90 micrometers across, or one tenth the width of a ballpoint pen’s tip. Leslie Nemo, Scientific American, "Even Tiny Phytoplankton Have Microbiomes," 19 Feb. 2021 Because small fish in the lakes eat zooplankton, a plunge in the diatom numbers would cause fish populations to crash. Tim Folger, National Geographic, "North America’s most valuable resource is at risk," 17 Nov. 2020 Going a step further, Martin proposed that using iron to trigger diatom blooms might help combat global warming. Emily Underwood, Smithsonian Magazine, "The Complicated Role of Iron in Ocean Health and Climate Change," 3 Jan. 2020 When a krill dies, the powerful enzymes in its belly that dissolve diatoms turn on and swiftly autodigest the body. Lucy Jakub, Harper's magazine, "A View to a Krill," 2 Mar. 2020 To reconstruct lake levels as far back as 18,000 years, scientists examined diatoms (a type of algae) collected from the bottom of the lake to see how fresh or brackish the water used to be. Emily J. Beverly, Quartz Africa, "In 100,000 years Lake Victoria has dried up three times—it could happen again," 26 Jan. 2020 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

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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Last Updated

4 Mar 2021

Cite this Entry

“Diatom.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diatom. Accessed 17 Apr. 2021.

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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

Britannica.com: Encyclopedia article about diatom

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