fee vs letter

fee

verb
  • To reward for services performed, or to be performed; to recompense; to hire or keep in hire; hence, to bribe. 

noun
  • A right to the use of a superior's land as a stipend for certain services to be performed, typically military service. 

  • An additional monetary payment charged for a service or good that is minor compared to the underlying cost. 

  • Synonym of fief: the land so held. 

  • An inheritable estate in land, whether absolute and without limitation to potential heirs (fee simple) or with limitations to particular kinds of heirs (fee tail). 

  • An inheritable estate in land held of a feudal lord on condition of performance of certain services, typically military service. 

letter

verb
  • To earn a varsity letter (award). 

  • To print, inscribe, or paint letters on something. 

noun
  • A size of paper, 215 mm × 280 mm. 

  • Literature. 

  • A size of paper, 8½ in × 11 in (215.9 mm × 279.4 mm, US paper sizes rounded to the nearest 5 mm). 

  • A symbol in an alphabet. 

  • A division unit of a piece of law marked by a letter of the alphabet. 

  • One who lets, or lets out. 

  • The literal meaning of something, as distinguished from its intended and remoter meaning (the spirit). 

  • A written or printed communication, generally longer and more formal than a note. 

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