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 Invasive mussels are filter-feeders, sucking out nutrients and plankton that native species rely on for food. Caitlin Looby, Journal Sentinel, 12 Sep. 2024 Colorado Parks and Wildlife broke the news of the mussels' arrival earlier this month after veligers, or larvae, were confirmed in plankton samples taken from several locations along the upper reaches of the river. Shaun McKinnon, The Arizona Republic, 22 July 2024 The buildup of acid in ocean waters reduces the availability of calcium carbonate, a key building block for the skeletons and shells of corals, plankton, shellfish, and many other marine organisms. Alan B. Sielen, Foreign Affairs, 15 Oct. 2013 Every May through November, giant manta rays come to feed, amassing by the hundreds, doing somersaults to catch plankton in their open mouths while snorkelers watch on in awe. Katie Lockhart, Robb Report, 9 May 2024 See all Example Sentences for plankton 

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 9 Oct. 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

More from Merriam-Webster on plankton

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