Someone probably already said this in this long thread, but "ortho" is a prefix from Greek and one of it's meanings is "corrected".
So the word means something like "corrected panchromatic", meaning corrected to mimic human perception of tone.
The original use of "orthochromatic" probably came from the same idea: making blue-only sensitive film more "visually correct" by adding green sensitivity.
Fuji is known for that kind of ambiguity, even with printing papers. But the correct answer is always somewhere officially, usually in the tech sheets, but sometimes you have to go further. Customer Service is basically tied to marketing, and has given me wrong answers several times. That's a common problem with a number of kinds of mfg, not just photo products.