am·​mo·​noid ˈa-mə-ˌnȯid How to pronounce ammonoid (audio)
: ammonite
Mesozoic ammonoids

Word History

First Known Use

1866, in the meaning defined above

Time Traveler
The first known use of ammonoid was in 1866

Dictionary Entries Near ammonoid

Cite this Entry

“Ammonoid.” Dictionary, Merriam-Webster, Accessed 29 Nov. 2023.

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