plural noun Te·trac·ti·nel·li·da

Definition of Tetractinellida

in some classifications

  1. :  a subclass or other division of Demospongiae comprising sponges with siliceous 4-rayed spicules or sometimes with desmas or without spicules

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Origin and Etymology of tetractinellida

New Latin, from Tetractina, a division of sponges in some classifications (from tetra- + -actina -actine) + -ella + -ida

Seen and Heard

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feeling or affected by lethargy

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