K-f-r in old Arabic means to "cover" : a farmer/tiller is a Kafer because he covers seeds with soil. But The Quran uses "Kafer" predominantly metaphorically as "one who covers" the claimed "revelation" - hence "disbeliever" hence enemy/target for elimination.
It is a sly sleight of hand to try and pretend that "k-f-r" begins and ends with its pre-Islamic language usage and implication. It does not matter if the language that founders of Islam learned, thought "kfr" a neutral word: what matters is how Islam's founders used it.
By that argument, "Nigger" in its original root form was not originally an offensive word - as it is derivation from Latin "nigrum" simply meaning black as a colour/pigment/hue. No proof Romans used it as pejorative. But in the American slave society dynamics it became offensive.
How a word comes to be used - becomes offensive or neutral. Its usage over the relatively short (compared to other major ones) existence of Islam has been overwhelmingly pejorative, offensive and intended to offend.
"nigrum"'s original meaning doesnt denote any active role on the part of the "niger", while "kfr" ascribes an active role in "hiding/covering up" Islam's founder's claimed "truth". Its travesty of academic honesty to claim that it remains neutral after such an usage.
