From Longman Dictionary of Contemporary Englishreverse gearreˌverse ˈgear noun [countable, uncountable] TTCthe position of the gears in a vehicle that makes it go backwards
Examples from the Corpus
reverse gear• After some time, he finally started the engine and crunched into reverse gear.• Thus the movement, seen from close by, appears to go into reverse gear.• The machine has no reverse gear.• In fact, it's surprising Honda hasn't included an electrically operated reverse gear. 