The definition of a mammoth is an extinct elephant from the Pleistocene epoch that had curved tusks and a sloping back.(noun)
A large extinct furry elephant type animal is an example of a wooly mammoth.
Mammoth is defined as something huge.(adjective)
When you make a really, really big mistake, this is an example of a mistake that would be described as a mammoth mistake.
See mammoth in Webster's New World College Dictionary
Origin: altered < Russ mamont, mammot < Yakut mamont, prob. < mama, earth: from the notion that the animal had burrowed in the ground
See mammoth in American Heritage Dictionary 4
Origin: Obsolete Russian mamut, mamot.
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