brevet vs obligation

brevet

noun
  • An authoritative grant or mark of recognition; a seal of approval. 

  • An organized, long-distance bicycle ride — not a race, but a test of endurance — which follows a designated but unmarked route passing through check points. 

  • A warrant from the government, granting a privilege, title, or dignity, as in France. 

  • A military document entitling a commissioned officer to hold a higher rank temporarily, but without an increase in pay. 

verb
  • To promote by brevet. 

obligation

noun
  • The fact of being obliged to, that is, grateful for, something. 

  • A social, legal, or moral requirement, duty, contract, or promise that compels someone to follow or avoid a particular course of action. 

  • A course of action imposed by society, law, or conscience by which someone is bound or restricted. 

  • The act of binding oneself by a social, legal, or moral tie to someone. 

  • A legal agreement stipulating a specified action or forbearance by a party to the agreement; the document containing such agreement. 

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