Lokah लोकः The world, a division of the universe.
Seven higher regions rising from the earth one above the other: Bhurlok, Bhuvarlok, Swarlok, Mahrlok, Janarlok, Taparlok, and Satyalok or Brahmlok.
Seven lower regions, descending from the earth one below the other: Atal, Vital, Satal, Rasaatal, Talaatal, Mahaatal, Paataal. Dictionary p483.