1. a broad, flat desert valley or basin surrounded by mountains, especially in the southwestern United States or Mexico
Usage: geographical term; common in southwestern U.S. and Mexican geography

Examples

• The Bolsón de Mapimí is a large desert basin in northern Mexico.
• Many bolsons in the American Southwest are characterized by sparse vegetation and dry lake beds.
• The bolson landscape features mountains that drain into a central valley with no outlet to the sea.
• Geologists study bolsons to understand desert hydrology and sediment deposition.
• The region's bolsons have been shaped by millions of years of erosion and tectonic activity.