n. a combination of a tractor{ 4 } hooked up to a trailer, forming a common type of truck{ 7 } used for carrying freight on highways. “Traffic was backed up for miles by a jackknifed tractor-trailer.” [ PJC ]

n. One who, or that which, trails. [ 1913 Webster ]

n. 1. a wheeled vehicle without a motor, designed to be drawn by a motor vehicle in front of it; specifically: (a) such a vehicle used on street railroads. Called also trail car. (b) the large wheeled wagon or van pulled by a tractor in a tractor-trailer combination. (c) a vehicle equipped as a mobile dwelling unit, pulled by an automobile or other mtor vehicle, and used as a dwelling when parked; -- also called a mobile home. (d) A wheeled motorless open wagon designed to carry a heavy object, such as a boat trailer. [ PJC ]

2. (Movies) A short blank segment of movie film attached to the end; -- used for convenient insertion of the film in a projector. [ PJC ]

3. (Movies) A short film consisting primarily of one or more short portions of a film, used in promotions or advertisements shortly before initial release of a film. [ PJC ]

4. A part of an object which extends some distance beyond the main body of the object; as, the trailer of a plant. [ 1913 Webster ]

trailer park. An area equipped to accommodate trailers{ 2 }, often with outlets supplying electrical power and water. Called also trailer camp, trailer court. [ PJC ]