Definition of "Officer" :

noun: any person in the armed services who holds a position of authority or command

"An officer is responsible for the lives of his men."

noun: someone who is appointed or elected to an office and who holds a position of trust

"He is an officer of the court."

noun: a person authorized to serve in a position of authority on a vessel

"He is the officer in charge of the ship's engines."

noun: a member of a police force

"It was an accident, officer."

verb: direct or command as an officer