An expanse of land suitable for livestock to wander and graze on.

( often plural ) land that naturally produces forage plants suitable for grazing but where rainfall is too low or erratic for growing crops 

any extensive area of land that is occupied by native herbaceous or shrubby vegetation which is grazed by domestic or wild herbivores.The vegetation of ranges may include tallgrass prairies, steppes (shortgrass prairies), desert shrublands, shrub woodlands, savannas, chaparrals, and tundras. Temperate and tropical forests that are used for grazing as well as timber production can also be considered rangeland. Rangelands thus occupy about 40-50 percent of the land area of the Earth