Nigger doesnt mean African. Well depending on who you ask that is. It has several meanings and uses. Some decided the world revolves around them and they alone own the word. Blacks pretty much decided the word can only be used by and about blacks and black mix breeds. If a non black uses it thats grounds for any black to act like a nigger. Thus letting the world know they absolutely are one. Plenty were using the word just fine long before some decided it can only be an insult about a certain race. For slang it can be used as a somewhat disrespectful way of applying emphasis. A bit like saying Bitch please. In your case it sounds like a foul mouthed youth was using it in this way while disrespecting his elders. If he was calling them the proper definition of nigger then saying nigger youre dumb is needlessly redundant. PS: Webster's Dictionary will argue against what ive just said but they are woke as can be and have an agenda to push. I personally saw the decline in the standard definition. It wasnt even that long ago.