Slant Rig (Slant-Hole Rig) : Drilling rig specifically designed to a drill a wellbore which is non-vertical at the surface; the mast is slanted and special pipe handling equipment is needed. (Bul D20)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}