What term describes a barrier separating opposing lanes of traffic?

The term that describes a barrier separating opposing lanes of traffic is "median." A median is specifically designed to enhance safety by creating a physical barrier between vehicles traveling in opposite directions. This helps to reduce the likelihood of head-on collisions and allows for a safer driving environment. Medians can also serve various other functions, such as providing space for turn lanes, pedestrian refuges, or landscaping.

While the other terms have distinct meanings, they do not accurately describe this barrier. A shoulder refers to the area beside the roadway, typically used for emergency stopping or breakdowns but not a separation between traffic lanes. A divider is often used interchangeably with median in some contexts but doesn't capture the defined role of a median as recognized in traffic safety terminology. An island usually refers to a raised area in a roadway, often at intersections, but does not specifically denote the linear barrier between opposing traffic.