Trusty horses is a term used to describe horses that are reliable and dependable. Cayuses and steeds are two words that can be used to refer to these types of horses. Cayuses are a type of horse that originated in the western United States and were used by Native Americans for transportation. Steeds are a type of horse that is strong and fast, and were historically used for riding and racing. Both cayuses and steeds are known for their trustworthiness and dependability, making them ideal for use as trusty horses.