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-2 in the Appendix of Indo-European roots.]
plank·tonic (-tŏnĭk) adj.
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.