noun Te·thy·um \ˈtēthēəm\

Definition of Tethyum

  1. :  a genus (the type of the family Tethyidae) of large muscular simple ascidians sometimes used for food

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Origin and Etymology of tethyum

New Latin, from Greek tēthyon sea squirt, from Tēthys, wife of Oceanus

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to cast off or become cast off

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