phragmocone

English

Etymology

From phragmo- +‎ cone.

Noun

phragmocone (plural phragmocones)

  1. (malacology) The chambered portion of the shell of certain cephalopods, divided by septa into camerae. [from 19th c.]
    • 2017, Danna Staaf, Squid Empire, ForeEdge, →ISBN, page 37:
      This ability to continuously add new buoyancy chambers to their phragmocones allowed ancient cephalopods to reach truly stupendous sizes.