sheik vs tribal sheikh

sheik

noun
  • The leader of an Arab village, family or small tribe. 

  • An Islamic religious cleric; the leader of an Islamic religious order. 

  • A romantic lover. (from the 1921 film The Sheik) 

  • An official title for members of the royal family as well as some prominent families. 

  • An Arab, especially one dressed in traditional clothing. 

  • An honorific for specialists in spirituality, for example in Sufism. 

tribal sheikh

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