(automotive, engineering) Having four wheels.

Having four wheels / Having a transmission that drives all four wheels.

off-roading in a vehicle with four-wheel drive

A four-wheeled vehicle with a drivetrain that allows all four wheels to receive torque from the engine simultaneously. / (uncountable) the type of vehicle transmission system.

plural of four-wheel drive

(automotive) four-wheel drive when used as an attributive adjective.