#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
  subtype:  #car_carrier  #semitrailer
  part of:  #trailer_truck__trailertruck__tractor_trailer__trucking_rig__articulated_lorry__semi  a truck consisting of a tractor and trailer together

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