5. Black cab. The famous London taxis are actually called 'hackney carriages' but in London we just call them 'black cabs/taxis'. London taxi drivers have to pass a special exam called the Knowledge to get their license so if you take a black cab, you can be sure the driver will know the way.
1907, shortening of taximeter cab (introduced in London in March 1907), from taximeter automatic meter to record the distance and fare (1898), from French taximètre, from German Taxameter (1890), coined from Medieval Latin taxa tax, charge. An earlier English form was taxameter (1894), used in horse-drawn cabs.
The taxicab is named after the taximeter, an instrument invented by Wilhelm Bruhn in 1891 that automatically recorded the distance traveled and/or the time consumed, thus enabling the fare to be accurately measured. The term cab derives from the cabriolet, a two-wheeled, one-horse carriage often let out for hire.
Cabbie Slang 101. Aside from the usual cabs, there are some folks who refer to these as sherbet. It originated from a rhyming term from Cockney “sherbet dab.” It is a sweet dissolving sugar that you can eat with a lollipop.