Definition of "daphnia" []

• Any of various water fleas of the genus Daphnia, some species of which are commonly used as food for aquarium fish. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "In the lab, Diamond recently showed a visitor how he exposed tiny water fleas called daphnia to titanium dioxide nanoparticles."
• "Try offering less dried foods, especially pellets, or offer some daphnia which is believed to act as a laxative."
• "Daphnia are used as "biomoitors"--if the daphnia start acting beserk, something is wrong with the water."