follow Dictionary.com

What does Boxing Day have to do with boxing?

ammonoid

[am-uh-noid] /ˈæm əˌnɔɪd/
noun
1.
any cephalopod mollusk of the extinct order Ammonoidea, from the Devonian to the Cretaceous periods, having a coiled, chambered shell.
Origin
1880-1885
1880-85; < New Latin Ammonoidea, equivalent to Ammon(ites) name of the order + -oidea -oidea; see ammonite2
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source
ammonoid in Science
ammonoid
  (ām'ə-noid')   
Any of various extinct cephalopods of the subclass Ammonoidea living from the Devonian to the Cretaceous Periods. Ammonoids had a symmetrical, coiled, chambered shell with angular sutures between the chambers. They are closely related to the nautiloids, including the modern-day chambered nautilus.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source

Word of the Day

Difficulty index for ammonoid

Some English speakers likely know this word

Word Value for ammonoid

13
16
Scrabble Words With Friends