adjective
Designating or relating to extinct ground sloths of the family Megalonychidae.
noun
A ground sloth of the family Megalonychidae.
Origin
1940s; earliest use found in Science. From scientific Latin Megalonychidae, family name (K. A. von Zittel in Handbuch der Palaeontologie IV. 133; from Megalonych-, taken as stem (after ancient Greek ὄνυχ-, ὄνυξ) of Megalonyx + -idae see -id).
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