Angle of Twist : The azimuth change through which the drill stem must be turned to offset the twist caused by the reactive torque of the downhole motor. (Bul D20)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}