Missourium
/mɪˈzʊərɪəm/Palaeontology. Now historical
noun
A large fossil skeleton (or composite of more than one skeleton) found in Missouri around 1839, originally claimed to be a new species but later identified as a mastodon (Mammut americanus).
Origin
Mid 19th century. From scientific Latin Missourium from the name of the U.S. state of Missouri, where the fossil skeleton was discovered + classical Latin -um, neuter ending.