argosy vs merchant marine

argosy

noun
  • A merchant ship. 

  • An abundant supply, boatload. 

  • A merchant flotilla, fleet. 

merchant marine

noun
  • A ship dedicated to commercial, rather than military, purposes. 

  • Synonym of merchant navy. The fleet considered as an entire combined force. 

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