From Longman Dictionary of Contemporary Englishsquad carˈsquad car noun [countable] SCPa car used by police on duty SYN patrol car
Examples from the Corpus
squad car• Glover opened his eyes and saw a white and blue squad car easing around the north bend on Mirror Lake Road.• They told me to get in the squad car and we drove right up to it.• Two young officers waited while he shaved and dressed before leading him to an unmarked squad car. 