airman vs ground pounder

airman

noun
  • A naval seaman, especially one in the U.S. Navy, who works on and/or handles aircraft. 

  • A pilot of an aircraft. 

  • A member of an air force. 

  • A person of a rank in the U.S. Air Force above airman basic and below airman first class. 

ground pounder

noun
  • A military soldier whose primary role is infantry or the use of ground-based materiel. 

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