(b) There was also a Pluteus (which we call Tablinum) a Place or Study, where the Pictures of their Ancestors, and their glorious Atchievements, were drawn or pourtray'd: On the other Side was the Kitchin, from whence they came into a Porch built about the Hall, or Cavedium, which, because `twas four-square, it was therefore surrounded with four Porticos, which may properly be called Walks or Piazzas.
Source: wiktionary