outbuilding
A small separate building on the same property as a house.
An outbuilding is a smaller structure that stands separate from a main house but belongs to the same property. Common outbuildings include garages, barns, sheds, workshops, and chicken coops. If your family stores lawn equipment in a small building behind your house, that's an outbuilding. If a farm has a barn for animals and a separate building for storing tractors, both are outbuildings.
Outbuildings serve purposes that don't need to happen inside the house itself. A potter might use an outbuilding as a studio. A carpenter might keep tools and lumber in one. On historical farms, people often built separate structures for different activities: one for making butter, another for smoking meat, and another for housing animals.
Outbuildings differ from additions or attached garages, which connect directly to the main house. A true outbuilding stands on its own, even if it's just a few steps from your back door. Some old estates have elaborate outbuildings like carriage houses or greenhouses, while modern homes might just have a simple storage shed tucked in the backyard.