noun Ci·o·na \ˈsīənə\

Definition of Ciona

  1. :  a genus (coextensive with the family Cionidae) comprising relatively large simple ascidians and including a single cosmopolitan species (C. intestinalis)


\ˈsīənə̇d, -ˌnid\ adjective or noun

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Origin and Etymology of ciona

borrowed from New Latin, perhaps derivative from the base of Greek kīon-, kī́ōn “pillar, uvula” — more at cion- Genus name introduced by the British clergyman and naturalist John Fleming (1785-1857) in The Philosophy of Zoology, or a General View of the Structure, Functions, and Classification of Animals, vol. 2 (Edinburgh, 1822), p. 512 (his Ciona intestinalis replacing Linnaeus’ Ascidia intestinalis). As with many of the dozens of taxonomic names introduced by Fleming, there is no suggestion of an etymology. One is left to guess as to whether the tunicate’s form suggested a pillar or uvula, or whether Fleming had a completely different classical (or non-classical) base in mind.

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feeling or affected by lethargy

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