Kid Rock seems to have no issue hurling the R-word on national television ... but the Special Olympics says he should think twice -- writing an open letter to him explaining the harm caused by using that word.
ICYMI ... Kid Rock appeared on "Jesse Watters Primetime" on Fox News last Friday -- and used the slur while telling Watters what he plans to be for Halloween.
Now ... in an open letter, Special Olympics Chief Inspiration Officer Loretta Claiborne is calling him out, urging him to take accountability.