— pleustonic /plooh ston"ik/ , adj.
/plooh"steuhn, -ston/ , n. Biol.
a buoyant mat of weeds, algae, and associated organisms that floats on or near the surface of a lake, river, or other body of fresh water.
[ 1940-45; pleus- ( pleûs ( is ) sailing, or pleus- aorist s. of pleîn to sail, go by sea) + -ton, on the model of NEKTON, PLANKTON ]