Why are Neanderthals considered a separate species from modern humans, Homo Sapiens, if they were able to interbreed with us?

If they can be considered a separate species then what does it even mean to be of a different species?

If they're a different species from us then why are White people and Niggers considered the same species, not to mention Kikes, Spics, Sand Niggers, and Chinks, etc?

What about other lifeforms?

Is this just the scientific establishment being afraid to acknowledge the obvious?

https://www.google.com/search?q=define+species
https://en.wikipedia.org/wiki/Interbreeding_between_archaic_and_modern_humans
https://en.wikipedia.org/wiki/Neanderthal#Classification