A meter - to display the cost of the journey !
A meter
The thing that counts how much money your going to pay.
A cab is a taxi car.
Rental, cab, taxi or limo.
One can buy a taxi meter from a number of local car accessories dealers. However a taxi meter can also be bought from online stores such as Taxi cab supply and Taxi Cab Electronics.
taxi cab limo
a special paint job (XD) and a machine that measures how far you've gone and how much it will cost.
One thing that a taxi cab would have that a regular car wouldn't is a meter. The meters determine how much a passenger will need to pay once they get to where they need to travel to.
The Checker Taxi Cab, check it out at this site, http://en.wikipedia.org/wiki/Checker_Taxi
That would be a 'taxi,' ...unless it was illegal, in which case it would be a 'gypsy cab'.
Passengers ride in the back seat.
In Britain, taxis are commonly known as "black cabs" or "hackney carriages", especially in London. Private hire vehicles (PHVs) are called "minicabs", which must be pre-booked. For a reliable taxi service in the UK, check out CabHit!