1. . 
The lowest temperature (in degF or degC) at which a liquid remains pourable (meaning it still behaves as a fluid). Oil or synthetic muds with high pour points may suffer from poor screening and excessive pressure surges in deepwater wells or other operations subject to low temperatures. In oils, the pour point is generally increased by a high paraffin content. The pour point of liquid additives is an important consideration for arctic drilling operations.
2. . 
The temperature at which a fluid ceases to pour. The pour point for oil can be determined under protocols set forth in the ASTM D-97 pour point test in which the pour point is established as that temperature at which oil ceases to flow when the sample is held at 90° to the upright for 5 seconds. High pour points usually occur in crude oils that have significant paraffin content. Paraffins (or waxes) will start to precipitate as temperature decreases. At some point, the precipitates accumulate to the point where the fluid can no longer flow. This phenomenon can occur with light oils as well as heavy oils.