ammonite

1 of 2

noun (1)

am·​mo·​nite ˈa-mə-ˌnīt How to pronounce ammonite (audio)
: any of a subclass (Ammonoidea) of extinct cephalopods especially abundant in the Mesozoic age that had flat spiral shells with the interior divided by septa into chambers
ammonitic adjective

Illustration of ammonite

Illustration of ammonite

Ammonite

2 of 2

noun (2)

Am·​mon·​ite ˈa-mə-ˌnīt How to pronounce Ammonite (audio)
: a member of a Semitic people who in Old Testament times lived east of the Jordan between the Jabbok and the Arnon
Ammonite adjective

Examples of ammonite in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
Most commonly seen in marine fossils, such as ammonites or trilobites, pyritization can produce highly detailed, metallic-looking fossils that are both scientifically valuable and visually striking. Nina Turner, Newsweek, 29 Oct. 2024 The exhibition achieves that goal with a thoughtful and heady combination of nearly 200 scientific and literary publications; artworks; and loans, including ammonites, trilobites and a cast of an ichthyosaurus skull. Anne Wallentine, Smithsonian Magazine, 8 Oct. 2024 Other mosasaur species preferred to dine on ammonites. Riley Black, Smithsonian Magazine, 2 May 2024 One hundred and thirty million years ago, countless ammonites of all shapes and sizes swam in the proto-Caribbean Sea alongside fishes and enormous marine predators. Santiago Flórez, Smithsonian Magazine, 6 Feb. 2024 See all Example Sentences for ammonite 

Word History

Etymology

Noun (1)

New Latin ammonites, from Latin cornu Ammonis, literally, horn of Ammon

Noun (2)

Late Latin Ammonites, from Hebrew ʽAmmōn Ammon (son of Lot), descendant of Ammon

First Known Use

Noun (1)

1726, in the meaning defined above

Noun (2)

1530, in the meaning defined above

Time Traveler
The first known use of ammonite was in 1530

Dictionary Entries Near ammonite

Cite this Entry

“Ammonite.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ammonite. Accessed 21 Nov. 2024.

Kids Definition

ammonite

noun
am·​mo·​nite ˈam-ə-ˌnīt How to pronounce ammonite (audio)
: any of numerous flat spiral fossil shells of mollusks related to the nautilus that are especially abundant in the Mesozoic era of geological history
ammonitic adjective

More from Merriam-Webster on ammonite

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