from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. The coiled, flat, chambered fossil shell of an extinct cephalopod mollusk that was abundant in the Cretaceous Period.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. An explosive prepared from ammonium nitrate; amatol
  • n. Any of an extinct group of cephalopods of the subfamily Ammonoidea; a fossil shell of such an animal

from the GNU version of the Collaborative International Dictionary of English

  • n. A fossil cephalopod shell related to the nautilus. There are many genera and species, and all are extinct, the typical forms having existed only in the Mesozoic age, when they were exceedingly numerous. They differ from the nautili in having the margins of the septa very much lobed or plaited, and the siphuncle dorsal. Also called serpent stone, snake stone, and cornu Ammonis.

from The Century Dictionary and Cyclopedia

  • n. One of the fossil shells of an extensive genus (Ammonites) of extinct cephalopodous mollusks (cuttle-fishes), of the family Ammonitidæ, coiled in a plane spiral, and chambered within like the shell of the existing nautilus, to which the ammonites were allied.
  • n. A name applied to certain explosive materials, patented by Favier, containing ammonium nitrate with other substances, chiefly nitro- or dinitro-naphthalene.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • n. one of the coiled chambered fossil shells of extinct mollusks


from The American Heritage® Dictionary of the English Language, 4th Edition

New Latin Ammōnītēs, from Latin (cornū) Ammōnis, (horn) of Amen, ammonite, genitive of Ammōn, Amen, from Greek.

from Wiktionary, Creative Commons Attribution/Share-Alike License

French ammonite, from Latin ammonis (cornua) "(horns of) Ammon".


  • The closest living relative of the ammonite is the chambered nautilus.

  • At one key point in the book, a man picks up an ammonite, the shell of an ancient mollusk, and marvels at its weight in comparison with the dress pocket he has pulled it from; at another, a young mother stumbles upon a valuable painting hidden behind a dressing table.

    Advance reader reviews of The Hand That First Held Mine by Maggie O'Farrell.

  • There are portraits and the wax seal, made from an ammonite, of the Very Reverend Dr. William Buckland, Dean of Westminster 1784-1856, a geologist who gave the first full description of a dinosaur, but who is better known for his stated ambition to eat a member of every living species of animal.

    Welcome to the Museum Of Weird and Wonderful

  • She was still on a public footpath, for she had obediently followed signs, some marked with a white ammonite and some with the yellow traditional lettering carved into wood.

    Margaret Drabble | Trespassing

  • One contained an ammonite, a fossilized nautilus shell.

    The Memory Palace

  • Then he lifted its head, wheeled it about by the ammonite, spirograph shells of its horns till its eyes, on stalks, looked back at its bones.

    Archive 2009-02-01

  • There's a point on the Corkscrew where for a split-second you can look ahead and to the side and get a cool view straight through the ammonite-spiral of the double loop.

    Round round get around I get around woooooo I get around

  • Next time you pick up a leaflet about Mr Wood's Fossils the main image will be my photo of a rather wonderful ammonite lagerstätte.

    Archive 2007-10-01

  • Upper Kimmeridgian ammonite faunas of the Wash area and a subzonal scheme for the lower part of the Upper Kimmeridgian.

    Dorset and East Devon Coast, United Kingdom

  • The standing totem with ammonite head attachments that extend like an exaggerated chignon is a universal female spirit fashioned by an acclaimed California artist who also happens to be a friend.

    The Virgin dialogue - an excerpt from the book: Agave Marias


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  • But which is more exciting ammonite or cummingtonite?

    March 4, 2009

  • So did I. Apparently this particular biblical tribe featured coiled chambered shells.

    August 29, 2008

  • I thought the Ammonites were a biblical tribe. :-)

    August 29, 2008

  • Look! I found one of mollusque's ancient ancestors!

    August 29, 2008