yellow vulture
n.— «Time-distance ticketing systems use multiple cameras spaced far apart on a freeway. Each car is photographed once as it enters the first section of road. Miles later a second photograph is taken that allows the vehicle’s average speed to be calculated from the time it took to travel between the two locations. In use in Britain under the trade name SPECS, these cameras are commonly referred to as “yellow vultures” and are among the most lucrative in the country.» —“Texas DOT to Install Federally Funded Highway Speed Cameras” theNewspaper.com June 11, 2007. (source: Double-Tongued Dictionary)