It differs from a veranda in being more architectural, and in forming more decidedly a part of the main edifice to which it is attached; from a porch, in being intended not for entrance but for an out-of-door sitting-room
1 An arcaded or colonnaded structure, open on one or more sides, sometimes with an upper story 2 An arcaded or colonnaded porch or gallery attached to a larger structure
A loggia is a roofed area attached to a house. an open area with a floor and a roof that is built on the side of a house on the ground floor. Hall, gallery, or porch open to the air on one or more sides. It evolved in the Mediterranean region as an open sitting room with protection from the sun. It is often a roofed, arcaded open gallery on an upper story overlooking a court, though it can also be a separate arcaded or colonnaded structure. In medieval and Renaissance Italy, it was often used in conjunction with a public square, as in Florence's Loggia dei Lanzi (begun 1376)