/ˈnektən/ /-tän/
Noun
1. Refers to the aggregate of actively swimming aquatic organisms in a body of water (usually oceans or lakes) able to move independently of water currents. (wikipedia.org)
2. A generic term for organisms in the ocean that are capable of swimming independently of currents. (wiktionary.org)
3. Free-swimming aquatic animals essentially independent of wave and current action. (merriam-webster.com)
4. The aggregate of actively swimming animals in a body of water ranging from microscopic organisms to whales. (wordnetweb.princeton.edu)
5. The assemblage of pelagic animals that swim freely, independent of water motion or wind. (global.britannica.com)