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zooplankton

[zoh-uh-plangk-tuh n]
noun
  1. the aggregate of animal or animallike organisms in plankton, as protozoans.
Compare phytoplankton.

Origin of zooplankton

First recorded in 1900–05; zoo- + plankton
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for zooplankton

zooplankton

noun
  1. the animal constituent of plankton, which consists mainly of small crustaceans and fish larvaeCompare phytoplankton
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for zooplankton
n.

1901, from comb. form of Greek zoion "animal" (see zoo) + plankton.

Online Etymology Dictionary, © 2010 Douglas Harper
zooplankton in Science

zooplankton

[zō′ə-plăngk′tən]
  1. Plankton that consists of tiny animals, such as rotifers, copepods, and krill, and of microorganisms once classified as animals, such as dinoflagellates and other protozoans.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.