first officer vs officer

first officer

noun
  • The executive officer, second in command of a naval vessel. 

  • Air Transport Auxiliary rank corresponding to Flight Lieutenant in the Royal Air Force. 

  • Women's Royal Naval Service rank corresponding to Lieutenant-Commander in the Royal Navy. 

  • The copilot of an aircraft. 

  • The chief mate of a merchant ship. 

  • The most senior civil servant in the United States Foreign Service, with responsibility for running an embassy under the authority of and reporting to the ambassador. 

officer

noun
  • A commissioned officer. 

  • A respectful term of address for an officer, especially a police officer. 

  • One who has a position of authority in a hierarchical organization, especially in military, police or government organizations. 

  • One who holds a public office. 

  • An agent or servant imparted with the ability, to some degree, to act on initiative. 

verb
  • To supply with officers. 

  • To command as or like an officer. 

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