gythja vs mambo

gythja

noun
  • A priestess of the modern Norse religion. 

mambo

noun
  • A voodoo priestess (in Haiti) 

  • A Latin-American musical genre, adapted from rumba, originating from Cuba in the 1940s, or a dance or rhythm of this genre. 

verb
  • To perform this dance. 

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