nek·ton (nĕktən, -tŏn′)
The collection of marine and freshwater organisms that can swim freely and are generally independent of currents, ranging in size from microscopic organisms to whales.
[Greek nēkton, neuter of nēktos, swimming, from nēkhein, to swim; see snā- in the Appendix of Indo-European roots.]
nek·tonic (-tŏnĭk) adj.
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