The largest landmasses, each holding many places under one name. Division at the coarsest scale.
Latin continens (holding together), present participle of continere (to hold together), from com- (together) + tenere (to hold); the largest landmasses, named for holding together as one connected body of land.
The Latin name is a present participle, not a noun for a shape — a continent is land caught in the act of holding itself together. The coarsest division on a map is still, at its root, a claim about what stays joined.