Fujinon" is Fujifilm's lens division. The "X" stands for "X-mount", where the letter X comes from "X is a letter which sounds cool" (in the catalog, they use the term 'X'treme,with no apparent hint of Gen X irony). And "XF" is either all lenses for this mount, or at least the first series of such lenses.
Next, we have the focal length and aperture — straightforward enough. But then all three are suffixed with this "R". I can't find any indication of what this might stand for in the literature, nor can I find it on older Fujinon lenses. So, what does it mean