A words meaning is derived only by its context. Observe:

That tree has no bark.
That dog has no bark.

Its even more obvious for what youre saying, because of the difference in spelling:

Hey nigga! ((said by person who is also black) = Greetings, fellow person with dark skin)
Hey nigger!((said by person who is white) = Give me your attention, scum who is lower in value to me due to skin color (meaning derived from history of word))

edit: I dont necessarily condone the use of the word, im just explaining...

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