black car

plural black cars

1. Londona black cab, a taxi that is only hailed from the street
2. New York Citya taxi that cannot be hailed from the street, but is called by placing a phone-in request; a call cab, a radio taxi

   To insure prompt service, large financial and legal concerns maintain accounts with as many as 10 black-car companies.

   1987 April 4, “'Black Cars' Take over Yellow Cabs' Radio Calls”, in New York Times

   1 more example

   Today the term "livery car" encompasses a range of private taxis, including car services that serve the working and middle classes, "black cars" that transport businesspeople, commuter vans in Queens and Brooklyn and vans for the disabled.

   1998 November 11, “Yellow Cabs and Black Cars: A Quick Lesson”, in New York Times

3. USA large government SUV with blacked-out windows
4. A limousine
5. A hearse