dak vs mailing

dak

noun
  • A post system by means of transport relays of horses stationed at intervals along a route or network, carrying mail and passengers. 

  • A dak bungalow. 

verb
  • To suddenly pull down someone's pants as a prank; to pants. 

mailing

noun
  • An act of sending mail. 

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