police car

:  govern

:  to control, regulate, or keep in order by use of police

:  to make clean and put in order

:  the internal organization or regulation of a political unit through exercise of governmental powers especially with respect to general comfort, health, morals, safety, or prosperity

:  control and regulation of affairs affecting the general order and welfare of any unit or area

:  the system of laws for effecting such control

:  a vehicle moving on wheels: such as

:  carriage, chariot

:  a vehicle designed to move on rails (as of a railroad)