Definitions:

1. A horse used to carry loads on its back, especially over rough or narrow terrain where carts or wagons can't go. NOUN
   • The traders used a packhorse to carry salt over the mountain pass.
2. A horse, mule, donkey, or pony used to carry goods on its back, usually in sidebags or panniers. NOUN
   • Each packhorse carried up to 200 pounds of supplies.
3. A working horse trained or used to transport goods, typically on trails, mountains, or remote paths, either led by a person or as part of a caravan of pack animals. NOUN
   • Before the railroad, mail was delivered by packhorse across the frontier.

Synonyms:

• pack animal