megalodon

noun

meg·​a·​lo·​don ˈme-gə-ləˌdän 

variants or Megalodon

plural megalodons or Megalodons

: a very large extinct shark (Otodus megalodon) of the Miocene and Pliocene epochs that is typically considered to be the largest fish ever to exist

So far we've only found teeth and vertebrae of megalodons. Like other sharks, most of their skeleton is made from cartilage which doesn't preserve well in the fossil record …

—Radha Krueger

The new study compared megalodon fossils with more than 150 living and extinct shark species. It found the megalodon may have had a longer, more slender body resembling that of the modern lemon shark, rather than the great white. It could have ranged between around 54 feet long and 80 feet long …

—Karissa Waddick

Word History

Etymology

borrowed from New Latin, specific epithet of Carcharias megalodon (later assigned to other genera), from Greek megal- megal- + -odōn "having teeth (of a specified nature)" — more at -odont

Note: The taxon was introduced by Louis agassiz in Recherches sur les poissons fossiles, tome 3, p.247 (illustrated with drawings of the teeth on tabula 29 of the accompanying Atlas volume). The volumes, published in Neuchâtel, Switzerland, were given the group date 1833-43. Tome 3 must have been released around 1837, because the illustration in the tome 3 atlas is referenced by Philip Grey Egerton in A Systematic and Stratigraphical Catalogue of the Fossil Fish in the Cabinets of Lord Cole and Sir Philip Grey Egerton (London, 1837) (unpaginated). Agassiz in his turn references Egerton in his description of the species, in which he gives "Carcharias megalodon Ag. in Egerton Catal." as a synonym of his Carcharodon megalodon Agass.

First Known Use

1927, in the meaning defined above