pond scum


Definition of pond scum

1 : any of various algae (especially spirogyra) or cyanobacteria
2 : a mass of tangled filaments of algae or cyanobacteria in stagnant waters

Examples of pond scum in a Sentence

Recent Examples on the Web And core samples from the watercourts contained a layer of dark gray sediment that appears to be on par with ancient pond scum. Alex Fox, Smithsonian Magazine, "In Ancient Florida, the Calusa Built an Empire Out of Shells and Fish," 2 Apr. 2020 The summer is hot, the water warm and people hoping to enjoy a pleasant day on Wisconsin’s lakes and rivers are instead turned away — disgusted at the soupy green blooms appropriately nicknamed pond scum. Lee Bergquist, Milwaukee Journal Sentinel, "It's peak algae season. Here's what you should know about a toxic form, 'blue-green algae'," 19 Aug. 2019 Algix, a Mississippi company, is now making plastics from algae — from pond scum, to be precise. Ruth Kassinger, BostonGlobe.com, "How slime will save the world," 26 July 2019 The idea behind the venture was radical: Use synthetic biology, a promising new technology that lets scientists reengineer the genetics of living organisms, to take on the fossil-fuel industry—and do the whole thing with pond scum. David Ferry, Newsweek, "The Promises and Perils of Synthetic Biology," 11 Mar. 2015

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'pond scum.' 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 pond scum

1864, in the meaning defined at sense 1

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Time Traveler for pond scum

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The first known use of pond scum was in 1864

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Cite this Entry

“Pond scum.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pond%20scum. Accessed 22 Oct. 2020.

More from Merriam-Webster on pond scum

Britannica.com: Encyclopedia article about pond scum

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