 -- We're taught in elementary school that there are seven continents on Earth -- Africa, Antarctica, Asia, Australia, Europe, North America and South America.

But geography textbooks across the world might have to add one more to that list -- Zealandia.

Zealandia is a continent that is 94 percent submerged underwater, which is why it took so long for geologists to identify it. The 6 percent that is above water comprises what many know as New Zealand and New Caledonia, according to a study in GSA Today, the journal of the Geological Society of America.

Zealandia spans almost 2 million square miles, a bit larger than India. And while the idea of a mostly submerged continent in the Pacific has been known in the science community for a while, it was only in the last two decades that researchers accumulated enough data and observations to classify it as the world's eighth continent.

In 1995, Bruce Luyendyk, a geologist teaching at the University of California Santa Barbara, coined the term “Zealandia” to describe New Zealand, New Caledonia and sections underwater that broke off from an ancient supercontinent, Gondwana.

“I wanted to just lump all of these masses together,” Luyendyk told ABC News today. “It was really just a convenient way to refer to this area.”