den

Den refers to a sheltered space used by animals as a home or lair, and to a room in a house set aside for private activities such as reading, working, or relaxing. The term is also used as an English place name or as a generic label for similar spaces in architecture.

In animals, a den is typically a secure, secluded space where a mother may rear young and store food. Dens can be underground burrows, caves, hollow trees, or man-made structures. Many species, including foxes, bears, and wolves, use dens seasonally to give birth or shelter.

In human dwellings, a den is a small room distinguished from more public living areas. A den often serves as a study, library, media room, or additional workspace. The design and furnishings of a den vary with purpose and culture.

In modern usage, DEN is the IATA airport code for Denver International Airport in Colorado, United States. Den also appears as a given name or nickname in various cultures, sometimes as a short form of Dennis or Danish names.