the largest reservoir (=a lake where water is stored before it is supplied to people's houses) in the US, on the Colorado River behind the Hoover Dam. Reservoir of the Hoover Dam, on the Arizona-Nevada border in the U.S. One of the largest man-made lakes in the world, it was formed by the damming of the Colorado River. Lake Mead is 115 mi (185 km) long and 1-10 mi (1.6-16 km) wide; it has a capacity of over 31 million acre ft (38 billion cubic m), with a surface area of 229 sq mi (593 sq km). It was named after Elwood Mead, commissioner of reclamation. Lake Mead National Recreation Area (established 1936) has an area of 2,338 sq mi (6,055 sq km) and extends 240 mi (386 km) along the river
a large reservoir in southeastern Nevada and northwestern Arizona that is formed by the Hoover Dam on the Colorado River; the center of a recreational area