Source : Webster's Revised Unabridged Dictionary (1913)

Piazza \Pi*az"za\, n.; pl. {Piazzas}. [It., place, square,
   market place, L. platea street, courtyard. See {Place}.]
   An open square in a European town, especially an Italian
   town; hence (Arch.), an arcaded and roofed gallery; a
   portico. In the United States the word is popularly applied
   to a veranda.

         We walk by the obelisk, and meditate in piazzas. --Jer.
                                                  Taylor.

Source : WordNet®

piazza
     n : a public square with room for pedestrians; "they met at Elm
         Plaza"; "Grosvenor Place" [syn: {plaza}, {place}]