eminent domain vs expropriation

eminent domain

noun
  • The right of a government over the private property within its jurisdiction. Usually invoked to compel land owners to sell their property in preparation for a major construction project such as a freeway. 

  • In feudalism, the legal interest or rights of a lord or superior in an estate in land held in fee, as opposed to the vassal's or tenant's interest. 

expropriation

noun
  • The act of expropriating; the surrender of a claim to private property; the act of depriving of private propriety rights. 

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