fiat vs firman

fiat

noun
  • An authority for certain proceedings given by the Lord Chancellor's signature. 

  • An arbitrary or authoritative command or order to do something; an effectual decree. 

  • Authorization, permission or (official) sanction. 

  • A warrant of a judge for certain processes. 

  • (Pertaining to) fiat currency. 

verb
  • To make (something) happen. 

firman

noun
  • A royal decree issued by a sovereign in certain historical Islamic states, especially by the Sultan of Turkey. 

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