diadem vs dominion

diadem

noun
  • Regal power; sovereignty; empire—considered as symbolized by the crown. 

  • A crown. 

  • An ornamental headband worn as a badge of royalty. 

  • An arch rising from the rim of a crown (rarely also of a coronet), and uniting with others over its centre. 

verb
  • To adorn with a diadem; to crown. 

dominion

noun
  • Power or the use of power; sovereignty over something; stewardship, supremacy. 

  • A kingdom, nation, or other sphere of influence; governed territory. 

  • predominance; ascendancy 

  • kingdom 

  • An order of angel in Christian angelology, ranked above virtues and below thrones. 

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