I dont think youre going to have much luck distinguishing between the two mathematical notions of geodesic on grammatical grounds  Geodesic may be used either as a noun or an adjective to refer to quantities which involve geodesics n  Likewise I have seen geodetic adj used in this way  although it is uncommon see for instance Penrose and Rindler Spinors and Spacetime  It appears that geodesic grid is just fine as a see also I had checked it before reverting  It seems to discuss geodesics in the sense this article talks about  Maybe I am missing something since you assure me that the geodesics over there are different from the geodesics here  Perhaps you need to remove the link from that article as well