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
the shell of any of these animals, commonly occurring as a fossil
an explosive consisting mainly of ammonium nitrate with smaller amounts of other substances, such as TNT
a nitrogenous fertilizer made from animal wastes
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
First recorded in 1600–10; ammo(nium) + nit(rat)e
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.
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Ammonite is the fourth Sednoid discovered to date.
From Space Scoop • Jul. 31, 2025
And, they are a nice change from the more solemn LGBTQ+ cinematic masterpieces we've seen fairly recently, like "Moonlight," "Call Me By Your Name," "Portrait of a Lady on Fire," "Ammonite" and "Carol."
From Salon • Aug. 25, 2023
Recognition for Anning grew after the 2020 release of the film Ammonite, starring Kate Winslet.
From Science Magazine • May 25, 2022
The pair are good friends and had appeared together on film in the period dramas Mary Queen of Scots and Ammonite.
From BBC • Sep. 22, 2021
“Its Latin name. Ammonite family. You can tell by these close tight ribs it's got, with these extra-fat ones every so often...”
From "Black Swan Green" by David Mitchell
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
