zooplankton
noun
zoo·plank·ton
ˌzō-ə-ˈplaŋ(k)-tən 
-ˌtän
plural zooplankton also zooplanktons
: freely floating or weakly swimming typically minute aquatic protozoans and animals (such as copepods, rotifers, and arrow worms) or the eggs or larvae of aquatic animals (such as anemones, mollusks, and fish) : plankton composed of animals
… numerous varieties of adult gamefish depend on zooplankton for a substantial portion of their diets throughout their lives.—
Byron W. Dalrymple
Byron W. DalrymplePhytoplankton exhale life-giving oxygen and are consumed as food by zooplankton and small fish, which, in turn, are eaten by larger fish.—Kenneth R. Weiss
Kenneth R. WeissRight whales eat zooplankton, which are tiny creatures that float along in the water column, by straining huge amounts of sea water through their baleen.—Wendall Waters
compare phytoplankton
Wendall WatersExamples of zooplankton in a Sentence
Recent Examples on the Web
Sunfish reside in open waters across the globe in tropical and temperate oceans and feed on mainly jellies and other gelatinous zooplankton like salps, squid, fish, crustaceans and algae.
—Amaris Encinas, USA Today, 5 Apr. 2025
Declines in zooplankton populations can harm fish and other marine animal populations that rely on them for food.
—Alexus Cazares-Nuesser, The Conversation, 25 Mar. 2025
Although a single penguin is capable of devouring thousands of krill in a single sitting, swarms of the zooplankton may detect disturbances in the water ahead of mealtime.
—Andrew Paul, Popular Science, 20 Mar. 2025
Invasive species such as the overbite clam consumed the zooplankton on which juvenile smelt had fed, toxic chemicals in farm runoff fouled the waters.
—Michael Hiltzik, Los Angeles Times, 14 Jan. 2025
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Amaris Encinas, USA Today, 5 Apr. 2025
Declines in zooplankton populations can harm fish and other marine animal populations that rely on them for food.
—Alexus Cazares-Nuesser, The Conversation, 25 Mar. 2025
Although a single penguin is capable of devouring thousands of krill in a single sitting, swarms of the zooplankton may detect disturbances in the water ahead of mealtime.
—Andrew Paul, Popular Science, 20 Mar. 2025
Invasive species such as the overbite clam consumed the zooplankton on which juvenile smelt had fed, toxic chemicals in farm runoff fouled the waters.
—Michael Hiltzik, Los Angeles Times, 14 Jan. 2025
See All Example Sentences for zooplankton
Cite this Entry
“Zooplankton.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/zooplankton. Accessed 22 Apr. 2025.
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zooplankton
noun
zoo·plank·ton
ˌzō-ə-ˈplaŋ(k)-tən
-ˌtän
: plankton that is composed of animals
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