: a flattened calcareous pouch or tube on either side of the middle line of the inner surface of the ambulacra of a blastoid, located within the cavity of the calyx, opening on the exterior by a small aperture, and presumed to form part of the respiratory system

Word History


hydr- + spire (coil)

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Dictionary Entries Near hydrospire

Cite this Entry

“Hydrospire.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hydrospire. Accessed 18 Apr. 2024.

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