plankton

PLANK-tun /ˈplæŋktən/
nounC1TOEFLIELTS
scientific

The small and microscopic organisms drifting or floating in the sea or fresh water.

They are defined by their inability to swim against a current, rather than by their size.

The story behind the word. Derived from the Greek 'planktos', meaning 'wandering'. It was coined by German physiologist Victor Hensen in 1887 to describe the organisms that drift at the mercy of the tides.

Word relationships

  • nekton: Organisms that can swim against currents, like fish and whales.

Commonly confused with

  • algae: Algae is a type of plankton (phytoplankton), but not all plankton are algae (some are tiny animals).

Collocations

  • phytoplankton
  • zooplankton
  • plankton bloom

Example sentences

  • "Plankton are the foundation of the entire marine food web." Marine biology lecture.
  • "Phytoplankton produce about half of the world's oxygen." Climate science.

Memory hook

Plankton 'plank' (float) in the water. Plankton = Drifters.

When not to use

Do not use for larger swimming animals like fish (nekton).

Fun facts

  • Whale sharks, the largest fish in the sea, eat some of the smallest organisms: plankton.

Related words

marine, aquatic, ecosystem

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