The adhesive friction of a wheel on a rail, a rope on a pulley, or the like; as, the car is stuck in the snow because it can;t get any traction.
In the context of this book the concept of achieving grip between the wheels and the ground without slip, skid or sinkage.
The UTQG traction rating is designed to help consumers compare the wet-road braking performance of a tire. Government guidelines specify the test conditions for testing traction on asphalt and concrete. All tests involve braking in a straight line. None of the tests measure traction while turning, resistance to hydroplaning, traction on snow or ice, dry road traction or any other type of "traction".