From Longman Dictionary of Contemporary Englishcar poolˈcar pool, carpool noun [countable] 1 DRIVEa group of people who agree to travel together to work, school etc in one car and share the cost2 TTCBa group of cars that a company or organization owns for its workers or members to use
Examples from the Corpus
car pool• The service operates rather like a car pool.From Longman Business Dictionarycar poolˈcar pool1 noun [countable]1British English a group of cars owned by a company or other organization that its members can useSYNmotor pool AmE2a group of car owners who agree to go to work together in one carhighways with ‘car pool lanes’ for vehicles carrying more than two passengers 