nig-nog vs swart

nig-nog

noun
  • A person of color, especially, a black person. 

  • A foolish person; hence, a raw and unskilled recruit. 

swart

noun
  • Black or dark dyestuff. 

adj
  • Of a dark hue; moderately black; swarthy; tawny. 

  • Black. 

verb
  • To make swart or tawny; blacken; tan. 

How often have the words nig-nog and swart occurred in a corpus of books? (source: Google Ngram Viewer )