4WD

car transmission system that provides engine power to all four wheels; car with a four wheel drive transmission

Four-wheel drive, 4WD, or 4x4 ("four by four") is a four-wheeled vehicle with a drivetrain that allows all four wheels to receive power from the engine simultaneously. In the United States, these cars are often, but not always, included in the broader sport utility vehicle  category. While many people associate the term with off-road vehicles, powering all four wheels provides better control on many surfaces, and is an important part of rally racing.
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Noun
1. a motor vehicle with a four-wheel drive transmission system
(synonym) four-wheel drive
(hypernym) motor vehicle, automotive vehicle
2. a transmission that provides power directly to all four wheels of a motor vehicle
(synonym) four-wheel drive
(hypernym) transmission, transmission system

Four Wheel Drive[SAE J1930]

4WD. FOUR-WHEEL DRIVE