plankton

noun

plank·​ton ˈplaŋ(k)-tən How to pronounce plankton (audio)
-ˌtän
plural plankton also planktons
: the passively floating or weakly swimming usually minute organisms (such as dinoflagellates, diatoms, copepods, radiolarians, and larval crustaceans and fish) of a body of water

Note: An individual organism found in plankton is technically referred to as a plankter.

… photosynthesizing plankton will grow at their intrinsic rates until nutrients become limiting, light is reduced by shading, and grazing organisms become abundant enough to check the increase …W. H. Berger
Almost all marine invertebrates, such as corals, clams, and starfish, reproduce by releasing microscopic larvae that drift in the plankton for a period ranging from minutes to months.Randy Olson et al.
Dense schools of menhaden … pour through these waters, toothless mouths … slurping up plankton and detritus …H. Bruce Franklin
The prolific zebra mussels have extremely efficient filtering systems, removing enormous quantities of plankton from the water …Nelson Bryant
see also phytoplankton, zooplankton
planktonic adjective
Other planktonic forms are grazers—tiny animals that filter algae and other organic matter out of the water and consume it. Wyoming Wildlife

Examples of plankton in a Sentence

fish that feed mainly on plankton
Recent Examples on the Web The significance of this is that up till now, the amount of carbon released to generate the PETM has been calculated from the aftereffects of the emissions—things like changes in ocean chemistry recorded in fossils of plankton that lived at the time. John Timmer, Ars Technica, 13 Jan. 2023 The abundance of certain types of plankton and krill, at the base of the ocean food chain, is linked with the Antarctic sea ice. Jonathan M. Gitlin, Ars Technica, 6 July 2023 Today, the entire plankton population in the surface layer of the world’s oceans is murdered by planktonic grazers and viruses every few days. Howard Lee, Ars Technica, 15 May 2023 Berndt argues that the 10–15 meters of sediment that filled the crater before the isotope shift and PETM-specific plankton appear represents just a short period. Eric Berger, Ars Technica, 4 Oct. 2023 Magni had explained to the class that clothes can retain traces of plankton, sediment and soil. Jordan Michael Smith, Smithsonian Magazine, 8 Jan. 2024 Enough marvelous biological innovations were discovered in 2023 to form a veritable parade: plankton that supercharged their photosynthetic abilities by repurposing one of their membranes, and underground microbes that learned to make oxygen in total darkness. Quanta Magazine, 19 Dec. 2023 According to the property, the thermal plankton are a biogenic treasure and harbor a wealth of natural minerals like sulfur, potassium, and magnesium. Michaela Trimble, Vogue, 27 Dec. 2023 The most popular attraction on Vieques is the bioluminescent Mosquito Bay, which glows blue at night as visitors kayak through its waters filled with phosphorescent plankton. Carley Rojas Avila, Travel + Leisure, 10 Nov. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'plankton.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

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

First Known Use

1889, in the meaning defined above

Time Traveler
The first known use of plankton was in 1889

Dictionary Entries Near plankton

Cite this Entry

“Plankton.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/plankton. Accessed 19 Mar. 2024.

Kids Definition

plankton

noun
plank·​ton ˈplaŋ(k)-tən How to pronounce plankton (audio)
-ˌtän
: the floating or weakly swimming animal and plant life of a body of water
planktonic adjective

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