police car vs prowl car

police car and prowl car both are nouns.

Word	Noun	Adjective	Verb	Adverb
police car	Yes	No	No	No
prowl car	Yes	No	No	No

As nouns, police car and prowl car are synonyms defined as:

police car and prowl car: a car in which policemen cruise the streets; equipped with radiotelephonic communications to headquarters

Other synonyms of police car include cruiser, patrol car, police cruiser, squad car.

police car (noun)	prowl car (noun)
a car in which policemen cruise the streets; equipped with radiotelephonic communications to headquarters	a car in which policemen cruise the streets; equipped with radiotelephonic communications to headquarters