plural noun

in some classifications
: a subclass or other division of Demospongiae comprising sponges with siliceous 4-rayed spicules or sometimes with desmas or without spicules

Word History


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

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Dictionary Entries Near Tetractinellida

Cite this Entry

“Tetractinellida.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Tetractinellida. Accessed 22 Jul. 2024.

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