Effective Torque is often referred to as wheel torque or torque to the wheels is primarily associated with automotive tuning. Torque can be measured using a dynamometer. Common units used in automotive applications can include ft·lbf and N·m. For more on units see: Foot-pound force.
Effective torque will often be 5-15% lower than the shaft or crank ratings of an engine due to a loss through the drivetrain.
For a general article please see: Machine torque.
References
Effective torque Wikipedia(Text) CC BY-SA