What term describes the width of a publicly maintained roadway open to vehicular travel?

The term that describes the width of a publicly maintained roadway open to vehicular travel is "highway." A highway typically refers to a major road designed for high-speed traffic, which can encompass various types of roadways including interstates and state routes. The term signifies not just the physical roadway but the entire design, including multiple lanes and management for both vehicle safety and efficiency.

While other terms like "road," "avenue," and "pathway" do relate to types of travel routes, they do not specifically convey the same level of infrastructure or capacity associated with a highway. A "road" could refer to any pathway for vehicles, typically of lesser scale or importance. An "avenue" often refers to a street in a city that may have a specific landscaping characteristic, and a "pathway" generally indicates a more limited passageway that may not accommodate vehicular traffic at all. Thus, "highway" is the most precise term for a publicly maintained roadway designed for vehicle travel at higher speeds.