What term describes a divided, controlled-access highway for through traffic?

The term that accurately describes a divided, controlled-access highway specifically designed for through traffic is "freeway." Freeways are engineered to allow for high-speed travel while minimizing interruptions typically associated with intersections, traffic signals, and cross traffic. They achieve this by incorporating ramps that facilitate the merging and diverging of vehicles without the need to stop, thus promoting the continuous flow of traffic.

The design of freeways also emphasizes safety by having features such as multiple lanes, dedicated exit and entrance ramps, and barriers separating opposing lanes of traffic. Such characteristics distinguish freeways from other road types, reinforcing their primary function of efficiently accommodating long-distance travel for vehicles.

While "interstate" usually refers to highways that are part of the national Interstate Highway System, which includes freeways, the term is broader and doesn't exclusively define the controlled-access aspect. "Expressway" can sometimes refer to similar roadways but may allow for some cross traffic or at-grade intersections, which does not align precisely with the controlled-access definition. "Highway" is a more general term that encompasses various types of roads, including local streets and not strictly controlled-access routes.