oligarch vs sovereign

oligarch

noun
  • A member of an oligarchy; someone who is part of a small group that runs a country. 

  • A very wealthy business owner who wields political power. 

  • A protoplanet formed during oligarchic accretion. 

sovereign

noun
  • One who is not a subject to a ruler or nation. 

  • A large, garish ring; a sovereign ring. 

  • A very large champagne bottle with the capacity of about 25 liters, equivalent to 33+¹⁄₃ standard bottles. 

  • A monarch; the ruler of a country. 

  • A gold coin of the United Kingdom, with a nominal value of one pound sterling but in practice used as a bullion coin. 

  • A former Australian gold coin, minted from 1855–1931, of one pound value. 

  • Any butterfly of the tribe Nymphalini, or genus Basilarchia, as the ursula and the viceroy. 

verb
  • To rule over as a sovereign. 

adj
  • Predominant; greatest; utmost; paramount. 

  • Exceptional in quality. 

  • Princely; royal. 

  • Having supreme, ultimate power. 

  • Exercising power of rule. 

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