Bitumen

Bitumen is a category of organic liquids which are highly viscous, black, sticky and wholly soluble in Carbon Disulfide. Asphalt and tar are the most common forms of bitumen.

In British English, 'bitumen' is often used interchangeably with both 'asphalt' and 'tar'. In American English, 'bitumen' is most commonly used in engineering jargon to explicitly include both asphalt and tar based materials.