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

Keep scrolling for more

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

Because many hyperpigmentation-fighting products can lighten skin tones altogether, Adoh made it a point to include a marine botanical called plankton extract that is safe for anyone to use. Akili King, Vogue, "Meet Epara, the Luxury Skin-Care Line Designed for Women of Color," 2 Feb. 2019 As the fishing boat, which police said was towing Mr. Chau’s kayak, made its way through the water Mr. Chau watched plankton glowing, his journal entry said. Rajesh Roy, WSJ, "American Missionary Killed by Isolated Tribe Wrote of Confrontation With the Group," 22 Nov. 2018 This type of jellyfish typically feeds on plankton, small fish and other tiny organisms. Jennifer Earl, Fox News, "Giant 'contracting' creature spotted on beach stuns family: 'It's alive'," 18 Sep. 2018 The sharks thrive on these tiny floating critters, chowing down by swimming close to the surface of the water, mouths agape, filtering the plankton in their specialized gills. Jason Daley, Smithsonian, "Massive Gathering of Mysterious Basking Sharks Found in Aerial Photos," 13 Apr. 2018 From microscopic plankton to sea horses, anemones and sharks, little survives inside the 30- to 100-foot radius of an explosion. Aurora Almendral, New York Times, "In the Philippines, Dynamite Fishing Decimates Entire Ocean Food Chains," 15 June 2018 Young visitors can test water quality and trawl for plankton with the Billion Oyster Project, learn angling with I Fish NY, make sea creature masks and other crafts, and enjoy live music and theater. Laurel Graeber, New York Times, "9 Things to Do With Your Kids in N.Y.C. This Weekend," 12 July 2018 Hungry microbes The measurements did find plenty of ancient methane at the bottom, although there was also young methane produced by the microbial breakdown of dead plankton (another source is atmospheric methane that mixes into the water). Scott K. Johnson, Ars Technica, "Submerged permafrost releasing methane, but not into the atmosphere," 24 Jan. 2018 Materials with Green Art Workshop Make your own insects, plankton, microbes, and other tiny beings with Green Art Workshop., "Kids listings," 12 July 2018

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.

See More

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

Keep scrolling for more

Learn More about plankton

Statistics for plankton

Look-up Popularity

Time Traveler for plankton

The first known use of plankton was in 1889

See more words from the same year

Keep scrolling for more

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

Keep scrolling for more

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).


showing courage and determination

Get Word of the Day daily email!

Test Your Vocabulary

Words for Summer: A Quiz

  • a closeup of a sunflower
  • Which of the following words means “of or relating to summer”?
Name That Thing

Test your visual vocabulary with our 10-question challenge!


Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!