I’ve always known fsck to mean “file system check” (I guess there’s officially a “consistency” in there), and while I can believe it was retconnned, what I stil

I’ve always known fsck to mean “file system check” (I guess there’s officially a “consistency” in there), and while I can believe it was retconnned, what I still don’t understand from the post is what the original, cheekier version actually abbreviated or where the “u” came from. (Though maybe, in the “GNU's Not Unix” vein, that is the joke?)