from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The act or an instance of sharing motor vehicle transportation with another or others, especially among commuters.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A form of transportation, other than public transport, in which more than one person shares the use of a vehicle, such as a van or car, to make a trip.
ride + sharing (Wiktionary)