#trailer  a large transport conveyance designed to be pulled by a truck or tractor
  supertype:  conveyance.instrumentality__transport  something that serves as a means of transportation
  part of:  trailer_truck
  subtype:  car_carrier__carcarrier  a trailer that can be loaded with new cars for delivery to sales agencies
  subtype:  semitrailer__semi  a trailer having wheels only in the rear; the front is supported by the towing vehicle

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