A carthorse is a heavy horse bred to pull loads. A great carthorse.
The breeds are enormous and unusually gentle, since a nervous horse of that size is useless. A carthorse can pull several times its own weight on a good surface.
1nouncarthorseA heavy horse bred to pull loads.
“The carthorse stood eighteen hands and never once shied.”
carthorse is a horse.
Old English craetehors, cart plus horse.
Old English
crætehors — a carthorse
Middle English
carthors
English, today
carthorse
From Middle English carthors, cartehors, from Old English crætehors (“a carthorse”), equivalent to cart + horse.
Etymology from Wiktionary, CC BY-SA