Hound is a label rather than a single breed. It covers scent hounds like Beagles, Coonhounds, Foxhounds and Bloodhounds, which follow a trail by nose, and sighthounds like Greyhounds and Whippets, which chase what they see. On adoption listings, a hound is most often a scent hound mix with long ears, a short coat and a big voice.
Many are friendly, easygoing with people and other dogs, and happiest with their noses down. They also tend to howl or bay, wander off after a scent and treat training as a negotiation. In Thornton, that means a secure fence at home and a leash on the trail, since a prairie dog or rabbit can override even a well-trained recall. Size and energy vary widely with ancestry, so each dog's listing says more than the label.