[ fahy-tuh-plangk-tuhn ]

  1. the aggregate of plants and plantlike organisms in plankton.

Origin of phytoplankton

First recorded in 1895–1900; phyto- + plankton

Words Nearby phytoplankton Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use phytoplankton in a sentence

British Dictionary definitions for phytoplankton


/ (ˌfaɪtəˈplæŋktən) /

  1. the photosynthesizing organisms in plankton, mainly unicellular algae and cyanobacteria: Compare zooplankton

Derived forms of phytoplankton

  • phytoplanktonic (ˌfaɪtəplæŋkˈtɒnɪk), adjective

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

Scientific definitions for phytoplankton


[ fī′tō-plăngktən ]

  1. Plankton consisting of free-floating algae, protists, and cyanobacteria. Phytoplankton form the beginning of the food chain for aquatic animals and fix large amounts of carbon, which would otherwise be released as carbon dioxide.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.