mailboat vs pouch

mailboat

noun
  • A boat used to transport mail. 

pouch

noun
  • A bulkhead in the hold of a vessel, to prevent grain etc. from shifting. 

  • Any pocket or bag-shaped object, such as a cheek pouch. 

  • A small bag usually closed with a drawstring. 

  • A cyst or sac containing fluid. 

  • A silicle, or short pod, as of the shepherd's purse. 

  • An organic pocket in which a marsupial carries its young. 

verb
  • To enclose within a pouch. 

  • To transport within a pouch, especially a diplomatic pouch. 

  • To swallow. 

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