n. [ F. officier. See Office, and cf. Official, n. ] 1. 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. “I am an officer of state.” Shak. [ 1913 Webster ]
2. (U. S. Mil.) Specifically, a commissioned officer, in distinction from a warrant officer or an enlisted man. [ 1913 Webster ]
Field officer,
General officer, etc. See under Field, General. etc. --
Officer of the day (Mil.), the officer who, on a given day, has charge for that day of the guard, prisoners, and police of the post or camp; abbreviated O. D., OD, or O. O. D. --
Officer of the deck, or
Officer of the watch (Naut.), the officer temporarily in charge on the deck of a vessel, esp. a war vessel. [ 1913 Webster ]