A tether is a rope, chain, or cord that ties an animal or object to a fixed point, keeping it from wandering too far away. Farmers might tether a goat to a stake in the ground so it can graze on grass within a circle but can't run off. Astronauts working outside their spacecraft wear tethers connecting them to the ship, preventing them from floating away into space.

The word also describes any connection that keeps something attached or limits how far it can go. A phone charging cable tethers your phone to the wall outlet. When you use your phone's internet connection to give your laptop internet access, that's called tethering because you're creating a connection between the devices.

People also use tether to describe invisible limits or connections. Someone might say they've reached “the end of their tether,” meaning they've run out of patience or energy, like a tethered animal that has walked as far as its rope allows. A person might feel tethered to their hometown by family connections, or tethered to their desk by an enormous pile of homework. In these cases, the tether isn't physical, but it still represents something holding you in place or limiting your freedom.