What is a barrier that separates two roadways, including interstates, called?

A median is the correct term for a barrier that separates two roadways, including interstates. Medians are designed to enhance safety by preventing vehicles from crossing into oncoming traffic, thus reducing the potential for head-on collisions. They can also provide a safe space for pedestrians and cyclists in certain road designs.

Medians can take various forms, such as raised structures, landscaping, or painted areas. By effectively separating traffic moving in opposite directions, they contribute substantially to the overall safety and organization of roadways. In contrast, shoulders are the sides of the roadway, dividers can refer more generally to barriers but are not specifically defined as separating different roadways, and lane markers only indicate where lanes begin and end without creating a physical barrier between them.