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Meaning of ammonoid

am•mo•noid

Pronunciation: (am'u-noid"), [key]
— n.
  1. any cephalopod mollusk of the extinct order Ammonoidea, from the Devonian to the Cretaceous periods, having a coiled, chambered shell.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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