"PI" used to stand for Plant Information when, in our early days, we were predominantly used as a data historian within plant operations. However, we've grown very far since then, and have expanded across many different industries, so these days "PI" doesn't stand for anything other than the brand name of our data infrastructure! If you're interested in the early days of OSIsoft, Chuck Thompson started a blog here on PI Square that would be informative PI (Legacy) Guy Introduction.
