plankton
Americannoun
noun
Other Word Forms
- planktonic adjective
Etymology
Origin of plankton
1890–95; < German, special use of neuter of Greek planktós drifting, equivalent to plang-, variant stem of plázesthai to drift, roam, wander + -tos verbid suffix
Explanation
If you set your pet goldfish free in a lake, he might dine on plankton instead of the food you sprinkle in his tank every day. Or, more likely, he might be dinner for a bigger fish. Lakes, seas, and oceans are full of plankton, most of which is so small it can't be seen without a microscope. Anything that floats near the surface is considered to be plankton, whether it's an animal, plant, or something smaller like bacteria, and it's one source of food for fish and whales. The Greek root, planktos, means "wandering or drifting."
Vocabulary lists containing plankton
Physical Geography - Introductory
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Something's Fishy: A Fresh Catch of Aquatic Words
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The Old Man and the Sea
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
They also identified other plankton species that evolved during the same interval.
From Science Daily • Mar. 15, 2026
This marker provides a more reliable way to measure the passage of time preserved in the geological record and allowed scientists to pinpoint when different plankton species first appeared in the fossil record.
From Science Daily • Mar. 15, 2026
Many calcareous plankton species that normally sink to the ocean floor disappeared during the extinction event.
From Science Daily • Mar. 15, 2026
Nitrosopumilus maritimus and closely related microbes make up about 30% of marine microbial plankton.
From Science Daily • Mar. 11, 2026
Fidelito admitted to gagging over plankton milk shakes, and Chacho said he used bad words when the wake-up bell went off.
From "The House of the Scorpion" by Nancy Farmer
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.