fog line
n.— «Resident Michael Reiskind noted that the Jamaicaway lacks edge-of-the-road striping—or “fog lines,” as he called them—on both shoulders of the road between Kelly Circle and Perkins Street. That means drivers have no visual cues about where the road ends and parkland and sidewalks begin.» —“Fewer cars crashing on parkways” by John Ruch Jamaica Plain Gazette (Massachusetts) Feb. 8, 2008. (source: Double-Tongued Dictionary)
Further reading
A listener who grew up in Newfoundland remembers her grandfather declaring the fog was thick as burgoo. Turns out burgoo was sailors’ slang for a gray, gelatinous oatmeal—exactly the right image for an impenetrable Newfoundland fog. The word appears...
In 1916, a small-town newspaper in Pennsylvania printed a fanciful item about a local gathering with a guest list that included, among others, Miss Ella Vader, Mr. Ray Zor, and other punny names. This is part of a complete episode. Transcript of...
This term is defined in the vehicle code of many states. I learned this term when I took drivers education over 15 yrs ago. While the use of fog lines may not be as prevalent in other countries (see Jamaica), its use in the United States is neither new nor worth of more attention. Its as old as the U.S. highway system and well documented.
David, “fog line” is not documented in any of the 12 mainstream English dictionaries I checked; therefore, I cited it here.