Ammonoid
/ˈæm.ə.nɔɪd/noun
Any extinct cephalopod of the subclass Ammonoidea, typically with a coiled, chambered shell.
Did you know?The name comes from the Egyptian god Amun, often shown with ram’s horns, because fossil ammonites were thought to resemble his coiled sacred emblem.
Etymological Timeline
Ancient Egypt
Egyptian
Amun
“A major god associated with hiddenness, later merged with ram imagery in Greco-Roman tradition.”
Ancient Greek
Greek
ammōniakos
“Of Ammon; used in reference to the Egyptian god Ammon/Amun.”
Late Latin
Latin
ammonites
“A stone or fossil associated with Ammon, especially a coiled shell-like fossil.”
18th Century
English
ammonite
“The fossil shell of an extinct coiled cephalopod.”
19th Century
English
ammonoid
“A broader scientific term for ammonite-like extinct cephalopods.”
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