This is a large mass of land made of a type of rock known as continental crust. Most geologists recognize six continents — Africa, Antarctica, Eurasia, Australia, North America and South America.
Much of continent’s land will be continuous. A cluster of small islands can’t be a continent. And a continent has to be big. But how big is big enough? There’s no precise definition. Australia, the smallest recognized continent, covers about 7.5 million square kilometers (2.9 million square miles). Greenland extends over about 2.1 million square km (about 810,000 square mi) of land. But it doesn’t count as a continent. Considered part of North America, it’s the world’s largest island. The cutoff for a continent is probably somewhere in between these two land masses.
In a sentence
Some scientists argue that New Zealand and its surrounding islands sit on a huge piece of continent crust that could be a new continent — Zealandia.