first%20officer

noun

1. 1

   The copilot of an aircraft.

2. 2

   The chief mate of a merchant ship.

3. 3

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

4. 4

   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.

5. 5

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

6. 6

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