Answer: commander

AnswerCrossword Clue
COMMANDERJason's rank on the Argo.
COMMANDERNaval officer.
COMMANDERRank below captain in the Navy
COMMANDERU.S.N. rank under captain
COMMANDER... in Chief (A.L. in 1861)
commanderone who commands
commanderA person in authority, esp. over a body of troops or a military operation
commanderA member of a higher class in some orders of knighthood
commanderA naval officer of high rank, in particular (in the US Navy or Coast Guard) an officer ranking above lieutenant commander and below captain
commander(in certain metropolitan police departments) The officer in charge of a division, district, precinct, or squad