#workhorse  a horse used for plowing and hauling and other heavy labor
  supertype:  horse__Equus_caballus  solid-hoofed herbivorous quadruped domesticated since prehistoric times
  subtype:  plow_horse__plough_horse  a horse used to pull a plow
  subtype:  draft_horse__draught_horse__draughthorse__dray_horse  horse adapted for drawing heavy loads
     subtype:  carthorse__cart_horse__drayhorse  draft horse kept for pulling carts
     subtype:  Clydesdale  heavy feathered-legged breed of draft horse originally from Scotland
     subtype:  shire_horse__shirehorse__shire  British breed of large heavy draft horse
     subtype:  poler__pole_horse  a draft horse harnessed alongside the shaft or pole of a vehicle
     subtype:  wheel_horse__wheelhorse__wheeler  a draft horse harnessed behind others and nearest the wheels of a vehicle
     subtype:  coach_horse__coachhorse  strong draft horse for drawing coaches
  subtype:  packhorse  a workhorse used as a pack animal
  subtype:  farm_horse__dobbin  a quiet plodding workhorse

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