plank·​ton | \ ˈplaŋ(k)-tən How to pronounce plankton (audio) , -ˌtän\

Definition of plankton

: the passively floating or weakly swimming usually minute animal and plant life of a body of water

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Other Words from plankton

planktonic \ plaŋ(k)-​ˈtä-​nik How to pronounce planktonic (audio) \ adjective

Examples of plankton in a Sentence

fish that feed mainly on plankton

Recent Examples on the Web

Most ocean dwellers, from plankton to fish to whales, live in the upper section of the ocean, squarely in the zone where temperatures are increasing quickest. Alejandra Borunda, National Geographic, "Ocean warming, explained," 14 Aug. 2019 But the new report released Monday, Aug. 12, 2019, by University of Michigan scientists says despite a drop-off of plankton caused by exotic mussels, the voracious carp could feed on other organic material when venturing into deeper waters. Washington Post, "Study: Asian carp could find plenty of food in Lake Michigan," 12 Aug. 2019 In their data visualizations, every species in a food web — from plankton to panthers — is reduced to a little ball, or node, and every feeding interaction becomes a line between them. Quanta Magazine, "She Finds Clues to Future Sustainability in Old Food Webs," 21 Mar. 2019 Despite their size — up to around 25 feet across — manta rays only eat plankton, shellfish and small fish. NBC News, "Manta ray rescued after seemingly approaching Australian snorkelers for help," 12 July 2019 Many of these cartilaginous swimmers eat fish, crustaceans, mollusks, plankton, krill, marine mammals, and other sharks—in short, humans are not on the menu. Elaina Zachos, National Geographic, "Why are we afraid of sharks? There's a scientific explanation.," 27 June 2019 According to the NOAA’s National Marine Mammal Laboratory, humpback whales are filter feeders, and survive off krill, plankton and small fish, such as anchovies — so capturing the sea lion was a complete mistake for the mammal. Claudia Harmata,, "Incredible Photo Captures Humpback Whale Almost Swallowing Up Sea Lion," 30 July 2019 Near Bermuda, biologist Laurence Madin has found that many in a single haul of plankton. David Doubilet, National Geographic, "The Sargasso Sea: Why it’s a living laboratory for change," 12 June 2019 As trillions of quagga mussels have spread across lakes Michigan and Huron, the invasive species has consumed much of the plankton, polluting the lake bottom with their waste and possibly providing these microbes a greater energy source. Tony Briscoe,, "Minuscule microbes wield enormous power over the Great Lakes. But many species remain a mystery.," 5 July 2019

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

1889, in the meaning defined above

History and Etymology for plankton

German, from Greek, neuter of planktos drifting, from plazesthai to wander, drift, middle voice of plazein to drive astray; akin to Latin plangere to strike — more at plaint

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Statistics for plankton

Last Updated

5 Sep 2019

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Time Traveler for plankton

The first known use of plankton was in 1889

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More Definitions for plankton



English Language Learners Definition of plankton

: the very small animal and plant life in an ocean, lake, etc.


plank·​ton | \ ˈplaŋk-tən How to pronounce plankton (audio) \

Kids Definition of plankton

: the tiny floating plants and animals of a body of water

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More from Merriam-Webster on plankton

Rhyming Dictionary: Words that rhyme with plankton

Spanish Central: Translation of plankton

Nglish: Translation of plankton for Spanish Speakers Encyclopedia article about plankton

Comments on plankton

What made you want to look up plankton? Please tell us where you read or heard it (including the quote, if possible).


to make a temporary encampment

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