necklace light
n.— «The lights on the bridge cables, in a colorful bit of shop talk, are called “necklace lights.” The phrase, or a variation of it, appears to have been around for a couple of decades (a caption on a 1981 New York Times photo by Fred R. Conrad of one of Mr. Cipriano’s bridge-maintenance forbears alludes to it).» —“Screwing In Light Bulbs, With Pride, on the Brooklyn Bridge” by Jake Mooney New York Times Dec. 28, 2007. (source: Double-Tongued Dictionary)