- the coiled, chambered fossil shell of an ammonoid.
- a nitrogenous mixture consisting chiefly of dried animal fats, usually obtained from livestock carcasses, and used as a fertilizer.
- an inhabitant of Ammon.
- of or relating to the Ammonites.
- 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
“cephalopod mollusk,” 1758, from French (Breyn, 1732), “better established” [Century Dictionary] by French zoologist Jean Guillaume Bruguière (c.1750-1798) in 1789, from Medieval Latin (cornu) Ammonis “horn of Ammon,” the Egyptian god of life and reproduction, who was depicted with ram’s horns, which the fossils resemble. The resemblance also was noted in ancient times.
- 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.