'Plankton' and 'planet' share a root — both are 'wanderers,' one in the sea, the other in the sky.
The diverse collection of tiny organisms that drift in the open water of oceans, seas, and freshwater bodies, unable to swim against currents, forming the base of most aquatic food chains.
Coined in German by the marine biologist Victor Hensen in 1887, from Greek 'planktos' (wandering, drifting), from 'plazein' (to drive astray, to lead sideways, to cause to wander), from PIE *pleh₂g- (to strike, to hit — hence to drive off course). The name reflects the defining characteristic of planktonic organisms: they are drifters, carried by currents rather than swimming under their own power. The Greek word is the same root that gives English
'Plankton' and 'planet' are etymological siblings — both derive from Greek 'plazein' (to wander). Plankton are 'the wanderers' of the sea; planets are 'the wanderers' of the sky. The ancient Greeks called the planets 'asteres planetai' (wandering stars) because they moved against the fixed backdrop of the