access road

road that affords access into and out of an area; short road giving access to an expressway

A frontage road (also access road, feeder, service drive, service road, outer road, and especially surface road) is a non-limited access road running parallel to a higher-speed road, usually a freeway, and feeding it at appropriate points of access (slip ramps). In many cases, the frontage road is a former highway already in existence when the limited access road was built. In other cases they may be built prior to construction of the highway. In urban areas, frontage roads are frequently one way roads when they exist on both sides of a highway. In more rural ones, roads are typically two-way.
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Noun
1. a short road giving access to an expressway; "in England they call an access road a slip road"
(synonym) slip road
(hypernym) road, route

RAMPA D'ACCESSO. RACCORDO AUTOSTRADALE. STRADA D'ACCESSO. STRADA SECONDARIA