- plankton (n.)
- 1891, from German Plankton (1887), coined by German physiologist Viktor Hensen (1835-1924) from Greek plankton, neuter of planktos "wandering, drifting," verbal adjective from plazesthai "to wander, drift," from plazein "to drive astray," from PIE root *plak- (2) "to strike, hit" (see plague (n.)). Related: Planktonic.
