: a genus (the type of the family Megatheriidae) of ground sloths found in the Pliocene and Pleistocene of America that are often of gigantic size and are related to the sloths and anteaters, the skull and dentition resembling those of the former and the vertebrae those of the latter

Word History


New Latin, from mega- + -therium

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Dictionary Entries Near Megatherium

Cite this Entry

“Megatherium.” Dictionary, Merriam-Webster, Accessed 30 May. 2024.

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