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prochloron

American  
[proh-klawr-on, -klohr-] / proʊˈklɔr ɒn, -ˈkloʊr- /

noun

Biology.
  1. any spherical, photosynthetic, prokaryotic microorganism of the genus Prochloron, occurring in subtropical and tropical habitats in symbiosis with various invertebrates, especially marine chordates, proposed as ancestral to the chloroplast of green algae and plants.


Etymology

Origin of prochloron

< New Latin < Greek próchlōron, neuter of próchlōros greenish ( pro- 2, chloro- 1 )