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The small or microscopic organisms that drift or swim weakly in a body of water, including bacteria, diatoms, jellyfish, and various larvae. Plankton is an important food source for fish and other larger organisms.

[German, from Greek, neuter of planktos, wandering, from plazein, to turn aside; see plāk- in Indo-European roots.]

plank·ton′ic (-tŏn′ĭk) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.planktonic - of or relating to plankton
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
The paleoceanographic conditions and its effects on the evolution of Cretaceous planktonic foraminiferal are evaluated from two stratigraphic sections i.e.
It's composed, to a large extent, of the mineral calcite (CaCO3) formed from the skeletons and shells of many planktonic organisms and corals.
Benz for their outstanding scientific contributions to marine planktonic, freshwater, and parasitic copepods, respectively.
This includes identification of molecules produced by escapin's oxidation of its substrates, L-lysine and L-arginine, and the cellular and molecular mechanisms whereby these molecules act as antimicrobial agents against planktonic bacteria and biofilms of bacteria.
The planktonic community is composed by a variety of organisms, since unicellular until pluricellular ones, ranging from tiny bacteria, algae, and protists to microscopic and macroscopic animals (such as fish larvae).
Preliminary Study on the Efficacies of Biocides on SRB Planktonic Growth.
The level of NO release from BIOC51 has proved sufficient for eradacting planktonic and biofilm-based bacteria, and can be delivered to the lungs as a dry powder or solution (e.g., nebulization).
Synergistic Effects of LFU and Antibiotics against Planktonic Bacteria
These organisms did not produce biofilms when grown alone aerobically; however, in the presence of aerobic/facultative anaerobic bacteria, these strict anaerobic species survived and grew in both planktonic and biofilm forms [18].