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am·mo·nite

(ămə-nīt′)

1. An extinct cephalopod mollusk of the order Ammonitida of the Permian to Cretaceous Periods, having a thick, usually coiled shell characterized by intricate suture patterns where the septa between individual chambers join the outer shell wall.

2. An ammonoid.

[New Latin Ammōnītēs, from Latin (cornū) Ammōnis, (horn) of Amun, ammonite, genitive of Ammōn, Amun, from Greek : from Egyptian jmn.]

am′mo·nitic (-nĭtĭk) adj.

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ammonite

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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