Bus alternative can refer to a variety of transportation options that are available as an alternative to taking the bus. These include TAXI (4 letters), RAIL (4 letters), Uber (4 letters), CAB (3 letters) and INS (3 letters). TAXI is a car service that can be hired for a fee, while RAIL is a form of public transportation that runs on tracks. Uber is a ride-hailing service that uses a mobile app to connect passengers with drivers. CAB is another term for TAXI, while INS stands for intercity night service, which is a type of bus service that operates at night.