A Tractor

1. (agriculture) A vehicle used in farms e.g. for pulling farm equipment and preparing the fields.
2. (US) A truck (or lorry) for pulling a semi-trailer or trailer.
3. Any piece of machinery that pulls something.
4. (aviation) An airplane where the propeller is located in front of the fuselage
5. (Britain, rail transportation) A British Rail Class 37 locomotive.
6. (archaic) A metal rod used in tractoration, or Perkinism.