Definitions for "Frontage road"
A roadway continuous to and generally paralleling an expressway.  Freeway, parkway, or through street so designed so as to intercept, collect and distribute traffic designating to cross, enter, or leave such facility and to furnish access to property which other wise would be isolated as a result of the controlled access features.
A road that parallels a larger highway and provides access to communities, stores, etc. Frontage/service roads limit the number of entrance and exit points onto a major roadway, reducing conflicts and improving safety.
a local road that runs parallele to an expressway and allows local traffic to gain access to property