Definition of zooxanthella in English:



  • A yellowish-brown symbiotic dinoflagellate present in large numbers in the cytoplasm of many marine invertebrates.

    • ‘These zooxanthellae may be found in many marine invertebrates, including sponges, corals, jellyfish, and flatworms, as well as within protists, such as ciliates, foraminiferans, and colonial radiolarians.’
    • ‘Both coral and sponge were sparse, and the former largely without color - giving symbiotic zooxanthellae.’
    • ‘The plants are tiny single-celled algae, the zooxanthellae or symbiotic dinoflagellates, that live within the tissues of corals in great numbers.’
    • ‘It is not known whether rugose corals had symbiotic photosymbiotic zooxanthellae as modern corals do.’
    • ‘The zooxanthellae in these corals are dinoflagellates, and it is suspected that there may be a relationship between their diversifications.’


Late 19th century: modern Latin, from zoo- ‘of animals’ + Greek xanthos yellow + the diminutive suffix -ella.