Any of various extinct cephalopods of the subclass Ammonoidea living from the Devonian to the Cretaceous Periods. Ammonoids had a symmetrical, coiled, chambered shell with angular sutures between the chambers. They are closely related to the nautiloids, including the modern-day chambered nautilus.
Find another word for ammonite. In this page you can discover 12 synonyms, antonyms, idiomatic expressions, and related words for ammonite, like: Asteroceras, trilobite, crinoid, ichthyosaur, bivalve, nautiloid, pyritised, brachiopod, ammonoid, belemnite and echinoid.