plural noun Sei·so·na·cea \ˌsīsəˈnāshēə\

Definition of Seisonacea

  1. :  a small order of Rotifera comprising elongated rotifers with weakly developed trochal disks that are epizoic on marine crustaceans

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Origin and Etymology of seisonacea

New Latin, from Seison, genus of rotifers + -acea

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