squad car vs motorcar

squad car and motorcar both are nouns.

Word	Noun	Adjective	Verb	Adverb
squad car	Yes	No	No	No
motorcar	Yes	No	No	No

As nouns, motorcar is a hypernym of squad car; that is, motorcar is a word with a broader meaning than squad car:

squad car: a car in which policemen cruise the streets; equipped with radiotelephonic communications to headquarters
motorcar: a motor vehicle with four wheels; usually propelled by an internal combustion engine

Other hypernyms of squad car include auto, automobile, car, machine.

squad car (noun)	motorcar (noun)
a car in which policemen cruise the streets; equipped with radiotelephonic communications to headquarters	a motor vehicle with four wheels; usually propelled by an internal combustion engine