Other forms: warhorses
A warhorse is a mount trained to carry a knight into battle. A great warhorse, mount the warhorse, an old warhorse.
The training was the expensive part: a horse must be taught not to shy at noise, crowds and other horses, which is against every instinct it has. Figuratively an old warhorse is a veteran, or a piece of music performed so often that everybody knows it.
1nounwarhorseA mount trained to carry a knight into battle.
“The knight climbed onto his warhorse, heavy in his armour, and rode towards the enemy.”
warhorse is a horse.
War plus horse, a plain compound from the sixteenth century.
From war + horse.
Etymology from Wiktionary, CC BY-SA