Any of the relatively dense hydrocarbons (denser than water) derived from petroleum, coal tar, and similar materials.
More example sentences
- Compared to petroleum, these heavy oils present additional refining and environmental problems because of the abundance of nitrogen, oxygen, and metal compounds found in them.
- The operation requires a steam generator, a plant to separate the heavy oil and water emulsion that is pumped to the surface and facilities to clean the water before it is recycled through the steam generator.
- A spokesperson said that, if the material in the water was a heavy oil, a clean-up operation would be needed.
Definition of heavy oil in:
- The US English dictionary