balloon tire definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
a wide, deep-walled pneumatic tire with relatively low air pressure to lessen the shock of bumps
balloon tire definition by American Heritage Dictionary
A wide pneumatic tire designed for full inflation at relatively low pressure, used especially in certain early bicycles and motor vehicles.