Tractor is described as a machine designed for towing. I.e. farm tractor, caterpillar tractor, highway tractor.
"Tractor" is in the NAICS Code "333112"
(Lawn and Garden Tractor and Home Lawn and Garden Equipment ManufacturingMulchers, lawn and garden-type, manufacturing)
"Tractor" is in the UNSPSC Code "14111504"
Tractor feed paper