letter carrier vs postman

letter carrier

noun
  • An employee of the post office who delivers mail (post) to, and collects it from, a residence or business, or from public mailboxes. 

postman

noun
  • someone who delivers the post (mail) to, and/or collects the post from, residential or commercial addresses, or from public mailboxes. 

  • One of the two most experienced barristers in the Court of Exchequer, who have precedence in motions, so called from the place where he sits, the other of the two being the tubman. 

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