Mammoth means extremely large, huge, or gigantic. A mammoth task is one that requires enormous effort, like reading all seven books in a long series in one month. A mammoth building towers over everything around it. Scientists might describe a mammoth discovery as one that changes how we understand the world.

The word comes from the extinct elephant relatives called mammoths, which roamed the Earth until about 4,000 years ago. These creatures stood up to 13 feet tall and weighed as much as 12,000 pounds, with enormous curved tusks that could grow 16 feet long. Their shaggy coats helped them survive Ice Age winters.

When paleontologists first discovered mammoth bones and tusks in Siberia centuries ago, they realized these animals must have been colossal, and the name became synonymous with anything impressively large. Today we use mammoth to describe undertakings, structures, or challenges of exceptional size: a mammoth construction project, a mammoth appetite, or a mammoth amount of homework. The word captures that sense of something so large it seems almost hard to believe, just like those ancient giants that once walked the frozen plains.