A sport utility vehicle or suburban utility vehicle (SUV) is a vehicle classified as a light truck, but operated as a family vehicle. They are similar to a large station wagon or estate car, usually equipped with four-wheel drive for on- or off-road ability. Some SUVs include the towing capacity of a pickup truck with the passenger-carrying space of a minivan or large sedan.
Popular in the late-1990s and early–mid-2000s, SUVs sales temporarily declined due to high oil prices and a declining economy. The traditional truck-based SUV is gradually being supplanted by the crossover SUV, which uses an automobile platform for lighter weight and better fuel efficiency, as a response to much of the criticism of sport utility vehicles. By 2010, SUV sales around the world were growing, in spite of high gas prices.
According to the Merriam-Webster dictionary, a "sport utility vehicle" is "a rugged automotive vehicle similar to a station wagon but built on a light-truck chassis". The "SUV" term is defined as "a large vehicle that is designed to be used on rough surfaces but that is often used on city roads or highways." The "SUV" acronym "is still used to describe nearly anything with available all-wheel drive and raised ground clearance."
There is no one definition for an SUV. Most government regulations simply have categories for "off-highway vehicles," which in turn are lumped in with pickup trucks and minivans as "light trucks." The auto industry has not settled on one definition.
Nevertheless, four-wheel-drive SUVs are considered light trucks in North America (and two-wheel-drive SUVs up to the 2011 model year) where they were regulated less strictly than passenger cars under two laws in the United States, the Energy Policy and Conservation Act for fuel economy, and the Clean Air Act for emissions. Starting in 2004, the United States Environmental Protection Agency (EPA) began to hold sport utility vehicles to the same tailpipe emissions standards as cars.