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plankton Syllabification: plank·ton
Pronunciation: /ˈplaNGktən/

Definition of plankton in English:


The small and microscopic organisms drifting or floating in the sea or fresh water, consisting chiefly of diatoms, protozoans, small crustaceans, and the eggs and larval stages of larger animals. Many animals are adapted to feed on plankton, especially by filtering the water. Compare with nekton.
Example sentences
  • The dung feeds microscopic plankton, which are consumed by worms and larvae.
  • The significance of this is that other species such as shellfish and crustaceans feeding in plankton could be affected.
  • The young remain in the water column feeding on plankton until they are around 50 mm in length.


Late 19th century: from German, from Greek planktos 'wandering', from the base of plazein 'wander'.

  • planet from Middle English:

    Early Greek astronomers observed certain heavenly bodies moving around the night sky in contrast to the stars, which stayed permanently in a fixed position in relation to one another. This is why they are called planets, from Greek planētēs ‘wanderer’. The Sun and the Moon were once thought of as planets too. Plankton, the term for small and microscopic organisms floating in the sea, comes via German from the related Greek word planktos, ‘wandering or drifting’. See also aeroplane



Example sentences
  • The younger planktic faunas are typical of the temperate conditions and depths from which the samples were collected.
  • Stable isotopic analyses were conducted on monospecific planktic and benthic foraminifera.
  • Questions arose as to whether cyclocystoids were benthic or planktic, sessile or free living.


Pronunciation: /plaNGkˈtänik/
Example sentences
  • The marine life benefits from planktonic nutrients, which means the area is teeming with both Mediterranean and Atlantic species.
  • This bacterial strategy is reasonable, since the above-mentioned advantage would be lost if the planktonic cell had peritrichous flagella.
  • The depth is recognized as that of the lower photic zone, the reproductive depth for planktonic foraminifera.

Words that rhyme with plankton


Definition of plankton in:

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