[awl-tuh-reyn] 
| a vehicle with treads, wheels, or both, designed to traverse varied, uneven terrain as well as roads. Abbreviation: ATV |
| all-ter·rain vehicle (ôl'tə-rān') n. Abbr. ATV A small, open motor vehicle having one seat and three or more wheels fitted with large tires. It is designed chiefly for recreational use over roadless, rugged terrain. |