Imperial vs sovereign

Imperial

noun
  • A large Bordeaux wine bottle with the capacity of about 6 liters, equivalent to 8 standard bottles. 

name
  • A census-designated place in Texas, United States. 

  • An unincorporated community in West Virginia, United States. 

  • A town in Saskatchewan, Canada. 

  • Imperial College London. 

  • An unincorporated community in Virginia, United States. 

  • A city, the county seat of Chase County, Nebraska, United States. 

  • A city in Imperial County, California, United States. 

  • A census-designated place in Pennsylvania, United States. 

sovereign

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

  • A large, garish ring; a sovereign ring. 

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

  • 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 Imperial and sovereign occurred in a corpus of books? (source: Google Ngram Viewer )