Definition of water flea
: any of various small active dark or brightly colored aquatic crustaceans (as a daphnia or cyclops)
First Known Use of water flea
WATER FLEA Defined for Kids
Definition of water flea for Students
: a tiny often brightly colored freshwater animal related to the crab and lobster
Learn More about water flea
Britannica.com: Encyclopedia article about "water flea"
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