noun (1)
am·​mo·​nite | \ ˈa-mə-ˌnīt How to pronounce ammonite (audio) \

Definition of ammonite

 (Entry 1 of 2)

: 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


noun (2)
Am·​mon·​ite | \ ˈa-mə-ˌnīt How to pronounce Ammonite (audio) \

Definition of Ammonite (Entry 2 of 2)

: a member of a Semitic people who in Old Testament times lived east of the Jordan between the Jabbok and the Arnon

Illustration of ammonite

Illustration of ammonite

Noun (2)

In the meaning defined above

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Other Words from ammonite

Noun (1)

ammonitic \ ˌa-​mə-​ˈni-​tik How to pronounce ammonitic (audio) \ adjective

Noun (2)

Ammonite adjective

Examples of ammonite in a Sentence

Recent Examples on the Web: Noun The couple, who own a farm in nearby Hays, had previously collected ammonites and tiny bones while hiking through the shortgrass prairie. New York Times, "Canada’s Newest Tyrannosaur Is Named for a ‘Reaper of Death’," 11 Feb. 2020 In addition, the amber contained the shells of squid-like critters called ammonites, which also lived in the sea. Matt Simon, Wired, "The Teeny-Tiny Flying Dino With a Mouth Full of Needle Teeth," 11 Mar. 2020 Giant mollusks with flanged shells that looked like alien cruisers disappeared forever, and many species of nautilus-like cephalopods called ammonites also went extinct. National Geographic, "Earth has had more major mass extinctions than we realized," 18 Dec. 2019 The download browser also features the fossilized jaw and skull of an unnamed dolphin species, the skull of a shrub ox unearthed in New Mexico’s Carlsbad Caverns, and a Jurassic Period ammonite. Meilan Solly, Smithsonian, "Ten Smithsonian Artifacts You Can 3-D Print," 27 Nov. 2019 But despite centuries of research, many mysteries still surround ammonites. Michael Greshko, National Geographic, "This ancient sea creature fossilized in tree resin. How'd that happen?," 13 May 2019 The Earp homestead is built on a bedrock of ammonite, which acts as a powerful revenant repellant. Jennifer Ouellette, Ars Technica, "Wynonna Earp’s wild season 3 finale takes the series to a whole new level," 2 Oct. 2018 In some cases -- some extremely rare cases -- ammonites can fetch between $40,000 to $50,000. CNN, "A 6-year-old girl goes digging in the dirt at her sister's soccer game -- and finds a 65 million-year-old fossil," 21 Mar. 2018 What the girl had found was the fossil of an ammonite, a sea creature that went the way of the dinosaurs millions of years ago. CNN, "A 6-year-old girl goes digging in the dirt at her sister's soccer game -- and finds a 65 million-year-old fossil," 21 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ammonite.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of ammonite

Noun (1)

1726, in the meaning defined above

Noun (2)

1530, in the meaning defined above

History and Etymology for ammonite

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

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Time Traveler for ammonite

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The first known use of ammonite was in 1530

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Cite this Entry

“Ammonite.” Dictionary, Merriam-Webster, Accessed 5 Jul. 2020.

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