plural noun

Definition of Orthonectida 

: an order or other division of Mesozoa comprising a number of rare parasites of the tissues and cavities of various invertebrates that alternate between an asexual plasmodial generation and a sexual generation resembling the nematogens of dicyemids but having numerous internal cells — compare dicyemida

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History and Etymology for Orthonectida

New Latin, from orth- + nect- + -ida

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exaggeratedly or childishly emotional

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