superior officer; commanding officer
Refers to a military or organizational superior; used in formal or hierarchical contexts.
He was my superior officer.
You must obey the orders of your superior officer.
He was promoted to a higher-ranking officer.
Soldiers must obey their superior officer's orders.
He reported the situation to his superior officer.
部下 means a subordinate, the direct opposite of 上官, a superior officer.
Compound of 上 (upper, superior) and 官 (official, officer).