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
Passengers ride in the back seat.
That would be a 'taxi,' ...unless it was illegal, in which case it would be a 'gypsy cab'.
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!