Trail"er (?), n. One who, or that which, trails.

Trail"er, n. A car coupled to, and drawn by, a motor car in front of it; -- used esp. of such cars on street railroads. Called also trail car.

Trail"er (?), n. One who, or that which, trails.

Trail"er, n. A car coupled to, and drawn by, a motor car in front of it; -- used esp. of such cars on street railroads. Called also trail car.

• (Aus, US): A small vehicle, usually open-topped, towed behind a car etc for carrying extra gear.
        At the end of the day, we put the snowmobiles back on the trailer.
  
• (UK): Any vehicle designed to be towed with the exception of a caravan.
  
• (US): A furnished vehicle hauled behind a car etc and used as a dwelling when stationary; a camper.
        We drove our trailer to Yellowstone Park.
  
• (US): A prefabricated home that theoretically can be towed to a new destination, but typically is permanently left in its original trailer park.
        The young couple's first home was in a trailer.
  
• (media) A preview of a film.
        Its trailer makes that movie seem like it would be fun.
       Note: in Aus. this term is gaining currency over the term preview under US influence.
  
• (computing): A usually invalid value used to signal the end of a list of data, often sorting last alphabetically ("ZZZZZ") or numerically ("99999") among all possible valid values; especially common with punched cards where the final card is called a "trailer card."
        The linked list terminates with a trailer record.
  
• (networking) the last part of a packet, often containing a check sequence
        The encapsulation layer adds an eight byte header and a two byte trailer to each packet.