vast inland region of the W U.S., between the Sierra Nevada & the Wasatch Mountains: the rivers & streams flowing into this region form lakes which have no outlet to the sea: c. 200,000 sq mi (517,998 sq km)
See Great Basin in American Heritage Dictionary 4
A desert region of the western United States comprising most of Nevada and parts of Utah, California, Idaho, Wyoming, and Oregon. John C. Frémont explored and named the area (1843-1845).