One who holds an office; a person lawfully invested with an office, whether civil, military, or ecclesiastical; as, a church officer; a police officer; a staff officer.
- One who holds an office of authority or trust in an organization, such as a corporation or government.
- One who holds a commission in the armed forces.
- A person licensed in the merchant marine as master, mate, chief engineer, or assistant engineer.
- A police officer.
- To furnish with officers.
- To command or manage as an officer.