If we're arguing semantics: isn't it an insult instead of a swear word?

I.e., is there a common use of the word not directed at a person? Like hitting your thumb with a hammer?

Funny story. We suspended a middle schooler earlier this year because he was heard using that word in close proximity to a black teacher. When approached, he swore he had stubbed his toe and cried out n*r in agony. The disciplinarian and I were discussing it and I was adamant that we could forgive his using any other verbiage, up to and including sob or the f-word in that context, but that I could never in a million years believe that anyone would use that particular slur after stubbing a toe or getting a paper cut.