letter vs masthead

letter

noun
  • A symbol in an alphabet. 

  • 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 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. 

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

  • To earn a varsity letter (award). 

masthead

noun
  • The logo of a broadcaster used in an ident. 

  • The top of a mast. 

  • A list of a newspaper or other periodical's main staff, contributing writers, publisher, circulation, advertising rates etc. 

  • The title (normally in a large and distinctive font) of a newspaper or other periodical at the top of the front page; (by extension) the publication itself or the rights to it. 

verb
  • To send to the masthead as a punishment. 

  • To furnish (a newspaper) with a masthead. 

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