A backyard is the area of land directly behind a house, typically enclosed by fences or natural boundaries. Most families use their backyards as outdoor living spaces where children play, adults garden, and families gather for cookouts or games.

Backyards vary enormously in size and character. Some are tiny patches of grass behind city townhouses, while others stretch across acres in rural areas. A suburban backyard might include a swing set, a vegetable garden, and a patio for grilling. Apartment dwellers often don't have backyards of their own, though some apartment buildings provide shared outdoor spaces.

The word also appears in useful phrases. When something happens in your own backyard, it's happening close to home, in your immediate surroundings. For example, discovering that a famous scientist lives in your neighborhood means having an expert in your own backyard. People sometimes use backyard to describe amateur or informal versions of activities, like backyard astronomy (stargazing from home rather than at a professional observatory) or a backyard mechanic (someone who fixes cars at home as a hobby rather than in a professional shop).