ammonite

¹ American  

[am-uh-nahyt] / ˈæm əˌnaɪt /

noun

1. the coiled, chambered fossil shell of an ammonoid.

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ammonite ² American  

[am-uh-nahyt] / ˈæm əˌnaɪt /

noun

1. a nitrogenous mixture consisting chiefly of dried animal fats, usually obtained from livestock carcasses, and used as a fertilizer.

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Ammonite ³ American  

[am-uh-nahyt] / ˈæm əˌnaɪt /

noun

1. an inhabitant of Ammon.

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adjective

1. of or relating to the Ammonites.

ammonite ¹ British  

/ ˌæməˈnɪtɪk, ˈæməˌnaɪt /

noun

1. any extinct marine cephalopod mollusc of the order Ammonoidea, which were common in Mesozoic times and generally had a coiled partitioned shell. Their closest modern relative is the pearly nautilus

2. the shell of any of these animals, commonly occurring as a fossil

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ammonite ² British  

/ ˈæməˌnaɪt /

noun

1. an explosive consisting mainly of ammonium nitrate with smaller amounts of other substances, such as TNT

2. a nitrogenous fertilizer made from animal wastes

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ammonite Scientific  

/ ăm′ə-nīt′ /

1. Any of the ammonoids belonging to the order Ammonitida and living during the Jurassic and the Cretaceous Periods. Ammonites had a thick, very ornamental chambered shell with highly defined, wavy sutures between the chambers.

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Other Word Forms

• Ammonitish adjective
• ammonitic adjective
• ammonitoid adjective
• pre-Ammonite adjective

Etymology

Origin of ammonite¹

1700–10; < New Latin Ammonites < Medieval Latin ( cornū ) Ammōn ( is ) (literally, horn of Ammon ) + -ītes -ite ¹; fossil so called from its resemblance to the horn of Jupiter Ammon

Origin of ammonite²

First recorded in 1600–10; ammo(nium) + nit(rat)e

Origin of Ammonite³

First recorded in 1605–15; Ammon + -ite ¹

Explanation

An ammonite is an extinct sea creature, a cephalopod distantly related to squids and octopuses. You can also use the word ammonite for the fossilized shells of these ancient animals. The last ammonites died out 66 million years ago, and some ammonite fossils are over 400 million years old. Although their closest living relations don't have hard shells, ammonites did. These ancient mollusks' shells were flat, coiled disks. Their name comes from the creatures' resemblance to a coiled ram's horn: Ammonite is derived from Ammon (or Amun), the name of an Egyptian god who was portrayed wearing ram's horns on his head.

Example Sentences

The name of this cuvée refers to the ammonite fossils in the ancient soils of the vineyards.

From Washington Post • Dec. 15, 2022

Fossils such as this opalized ammonite can develop gradually when a mixture of water and silica permeates deeply buried shells, bones or teeth left behind after other remains rot away.

From Scientific American • Sep. 5, 2022

Enter Nipponites mirabilis, a species of ammonite straight out of an M.C.

From New York Times • Dec. 10, 2021

“Live ammonite, ripped apart by the tsunami—they don’t travel well,” he said.

From The New Yorker • Mar. 29, 2019

“It's a type of ammonite, isn't it, Dad?”

From "Black Swan Green" by David Mitchell