Dervish vs gymnosophist

Dervish

noun
  • A member of a Sufi Muslim ascetic fraternity of mendicant friars. 

  • A citizen or inhabitant of Darawiish (circa 1895–1920 C.E.), the Dhulbahante anti-colonial polity geographically corresponding with Khaatumo. 

gymnosophist

noun
  • One of a school of ancient Indian ascetic philosophers, reported in antiquity, who wore little clothing; a mystic. 

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