Where does the term “pi fonts” come from? And who was the first to use or popularize it?
I always assumed it was an odd abbreviation of “pictogram”, but it was never clear because the term is sometimes used to describe any non-alphanumeric/symbol font. If pi does indeed stand for pictogram, that would limit its relevance to a specific subset of symbol fonts – for example, mathematical symbols aren't pictograms.
That doesn't really match up with the kinds of fonts I typically think of when I hear the term “pi” either, which tend to be be more technical and abstract than they are pictorial. Maybe there's a connection to the mathematical concept of pi?