Continent

A continent is a large terrestrial tectonic plate in a planet, moon, or asteroid. A continent may contain a few dozen countries if inhabited. Smaller tectonic plates are sometimes called microcontinents. There is no clear cut definition of them.

Properties
On earth, there is great variation in the sizes of continents; Asia is more than five times as large as Australia. The largest island in the world, Greenland, is only about one-fourth the size of Australia. The continents differ sharply in their degree of compactness. Africa has the most regular coastline and, consequently, the lowest ratio of coastline to total area. Europe is the most irregular and indented and has by far the highest ratio of coastline to total area.