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Orthonectida Line breaks: Ortho|nec¦tida
Pronunciation: /ˌɔːθə(ʊ)ˈnɛktɪdə/

Definition of Orthonectida in English:

plural noun

A minor phylum of mesozoan worms which are internal parasites of a range of marine invertebrates.
Example sentences
  • They are now believed to be made up of two, possibly unrelated, groups: the Dicyemida and Orthonectida.
  • As it turns out, the Orthonectida are almost certainly metazoans, particularly under our stem group definition; but it's anyone's guess whether they, or any other members of the mysterious Mesozoa, are also bilaterians.


Modern Latin (plural), from Greek orthos 'straight' + nektos 'swimming' (see nekton).



noun& adjective
Example sentences
  • In some orthonectids, circular and longitudinal muscles occur beneath the epidermis.

Definition of Orthonectida in:

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