second lieutenant

/S EH1 K AH0 N D L UW0 T EH1 N AH0 N T/
noun
  1. 1

    The lowest rank of a commissioned army officer, below a lieutenant.

  2. 2

    The lowest rank of a commissioned officer in the United States Army, United States Air Force, or United States Marine Corps, below a first lieutenant. The rank of second lieutenant is equivalent to the naval rank of ensign.

Source: https://en.wiktionary.org/wiki/second%20lieutenant