ammonite(redirected from Ammonoidea)
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1. A member of a Semitic people inhabiting ancient Ammon, mentioned frequently in the Bible.
2. The Semitic language of the Ammonites.
[From Late Latin Ammōnītēs, the Ammonites, from Hebrew 'ammônî, Ammonite, from 'ammôn, Ammon, perhaps of Canaanite origin; see ʕmm in Semitic roots.]
1. An extinct cephalopod mollusk of the order Ammonitida of the Permian to Cretaceous Periods, having a thick, usually coiled shell characterized by intricate suture patterns where the septa between individual chambers join the outer shell wall.
2. An ammonoid.
[New Latin Ammōnītēs, from Latin (cornū) Ammōnis, (horn) of Amun, ammonite, genitive of Ammōn, Amun, from Greek : from Egyptian jmn.]
am′mo·nit′ic (-nĭt′ĭk) adj.
1. (Palaeontology) 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
2. (Palaeontology) the shell of any of these animals, commonly occurring as a fossil
[C18: from New Latin Ammōnītēs, from Medieval Latin cornū Ammōnis, literally: horn of Ammon]
1. (Elements & Compounds) an explosive consisting mainly of ammonium nitrate with smaller amounts of other substances, such as TNT
2. (Elements & Compounds) a nitrogenous fertilizer made from animal wastes
[C20: from ammo(nium) + ni(tra)te]
the coiled, chambered fossil shell of an ammonoid.
[1700–10; < New Latin Ammonites= Medieval Latin (cornū) Ammōn(is) literally, horn of Ammon1 + -ītes -ite1]
am`mo•nit′ic (-ˈnɪt ɪk) adj.
am•mon•i•toid (əˈmɒn ɪˌtɔɪd) adj.
a member of a Semitic people inhabiting ancient Ammon.
Any of the coiled fossil shells of a group of extinct mollusks related to the nautilus. Ammonites were especially abundant during the Mesozoic Era.