Green’s Dictionary of Slang

1. (US) to do menial work.

c.1824–38

G. Furman Antiquities L.I. 228: The settlers who owned a few slaves employed them in this work; and hence, this process [grinding grain by samp mortar] was vulgarly called in that part of the State ‘niggering corn’ [DA].

2. (UK Und.) to work as a nigger minstrel.

1893

P.H. Emerson Signor Lippo 27: Well, Dukey, this is better than niggering.