water flea


: any of various small active dark or brightly colored aquatic crustaceans (such as a daphnia or cyclops)

Example Sentences

Recent Examples on the Web But this one is special: The genome of the water flea contains a staggering 30,907 genes—the most ever seen in an animal, and about 8,000 more than humans have. Andrew Moseman, Discover Magazine, 4 Feb. 2011 Species like the fishhook water flea and the bloody red shrimp — which could be even worse than invasive carp. Juanpablo Ramirez-franco, Journal Sentinel, 26 Aug. 2022 The next year, in 1982, overseas ships were blamed for bringing into the lakes the spiny water flea that has ravaged native zooplankton and the little fish that depend upon them. Dan Egan, jsonline.com, 2 Sep. 2021 Andrei Savitsky's video of a water flea giving birth to cubs won third place in the competition. Elizabeth Gamillo, Smithsonian Magazine, 23 Aug. 2021 Euplotes skitters nimbly along surfaces atop cirri like some sort of Close Encounters–class water flea. Jennifer Frazer, Scientific American, 22 May 2021 The spiny water flea was first identified in North American in 1984 in Lake Huron. Popular Science, 17 Feb. 2021 Their numbers have been decimated by a fierce invasive predator, the spiny water flea. Tim Folger, Environment, 2 Dec. 2020 Other invaders arrived by the same route as the spiny water flea, in the ballast tanks of oceangoing freighters. Tim Folger, Environment, 2 Dec. 2020 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'water flea.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1687, in the meaning defined above

Time Traveler
The first known use of water flea was in 1687

Dictionary Entries Near water flea

Cite this Entry

“Water flea.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/water%20flea. Accessed 31 Jan. 2023.

Kids Definition

water flea

: any of various small active dark or brightly colored freshwater crustaceans (as a daphnia)

More from Merriam-Webster on water flea

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