circumvallation vs kraal

circumvallation

noun
  • A rampart or other defensive entrenchment that entirely encircles the position being defended. 

kraal

noun
  • An enclosure for livestock. 

  • In Central and Southern Africa, a small rural community. 

  • In Central and Southern Africa, a rural village of huts surrounded by a stockade. 

verb
  • To enclose (livestock) within a kraal or stockade. 

How often have the words circumvallation and kraal occurred in a corpus of books? (source: Google Ngram Viewer )