Slang phrase nigger in the woodpile "a hid motive or not known factor affecting a scenario within an adverse way" [OED 1989] is attested by 1800; Thornton's "American Glossary" (1912) defines it as "A manner of accounting with the disappearance of gasoline," as a result "an unsolved secret.In summary, the use of the phrase "Niga" isn't appropriate,