General Definition: 1. Any kind of wheeled unpowered vehicle which is towed by a powered vehicle (car, truck or tractor), like a tailer or caravan. As a Noun: 1. A special bar found at the back of a vehicle to which another vehicle (eg, trailer or caravan) is attached when towed. English = tow bar. 2. As a Verb or Adjective: 1. Of a vehicle, to pull another vehicle behind it. English = tow.