Undersaturated Fluid : A liquid capable of holding additional gaseous components in solution or a vapor capable of holding additional liquid components in solution at the specified pressure and temperature. (RP 44)
The Mudblogger (Oilfield, Energy and Related Photographs), Oil Field Glossary, TX, USA 2014. http://mudblogger.com/oilfield-glossary/, (Oil - Amer) {777}