In learning something about the history of American porches (front porches have a strong Afro-Caribbean history, BTW), I read a source document from a colonial New Yorker writing to a New Englander about a design custom that had come up from the south. He used the word peazer and described it, saying it was such a wonderful addition to a living space that he couldn't imagine having a house without one now. It took quite a bit of reading before I figured out that he was spelling phonetically, as even educated people did in those days, and was writing about a piazza. The -er ending reminded me of my grandfather's second wife, my Gramma Helen Bates, an odd and not classically educated person from central Massachusetts, who always called the three-season porch the piazzer. I wondered at the time if it was some bizarre affectation of folk over to Leominster trying to sound elegant and Italian, or perhaps even picked up from Italian immigrants to her small city. I suddenly suspected it had been in use a lot longer.
The Shorter Oxford tells me exactly that, that piazza was an Italian market or square the word used in English by the late 16th C. It came to refer to a veranda by the early 18th, especially if covered, chiefly in the US. The word could easily have expanded in meaning from covered veranda to unheated porch. Now that I recall, the term was also used for the connecting porch from a house to a garage. I can't remember which of the families in my acquaintance used the term that way, but I think they were many. As a dialect form, piazza may have fallen out of use as a word for a veranda at all in New England, so that the single word describes diffferent features north and south. It makes entire sense that verandas would have gotten going in the south much earlier, but by the time they reached New England the idea of enclosing them a bit would make sense. Everyone adapts to local conditions.
The cats, all of them, lived on the piazzer, along with a piano she would bang on every day, thinking we were entertained. She had been a clothing buyer for a better store (so she said) before her late marriage, and there were also stacks of old magazines with knitting patterns and other clothing directions. In my mind, they all had pictures of kittens sitting in baskets with balls of yarn. They we so cunnin', she said. It had an odd smell, probably camphor, mixed with cat something and magazine must. Not terrible, just odd. I think little of this was in the minds of Italian architects in the Middle Ages.