Tethered describes something that's tied up, like a horse that's tethered to a fence or a dog that's tethered to the person who is walking it.
Whenever you confine a person or an animal to keep them in one place, they're tethered. A bank robber might leave his hostages tethered together in the vault, and you might keep your fence-jumping dog tethered to the porch when she's out in your yard. The root word is the Old Norse tjoðr, tether, which was used only as a noun to describe the rope that ties animals until the late 15th century, when the verb form developed.
