Side-Racking Pocket : An enlargement of one side of the wellbore made to facilitate changing the direction of the wellbore. The wellbore enlargement is usually accomplished by use of jetting action. (Bul D20)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}