What is "officer of the day"

Officer \Of"fi*cer\, 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.

2. (U. S. Mil.) Specifically, a commissioned officer, in distinction from a warrant officer or an enlisted man.

   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.

The officer of the day (OOD) is a detail rotated each day among the unit/post's commissioned officers and/or warrant officers. The OOD oversees security, guard, and law enforcement considerations as well as conducts inspections of dining facilities. Even if the officer has never served as a MP or is not qualified to serve as a provost marshal, all officer basic training courses include the training necessary to perform this duty. Specialist officers such as dentists, physicians, and lawyers have their Officers of the Day who are responsible for carrying out the various missions of their respective specialties after the duty day is over. The dental officer of the day is called the DOD; the medical officer of the day is called the MOD.

In the Royal Navy, and other navies based upon this structure, the OOD has been delegated authority from the Commanding Officer of a ship or establishment to ensure the routine running of the vessel is carried out. Unlike the USN's OOD, the Officer of the Day is primarily a position used when a warship is alongside in port. Other duties include ceremonial duties (such as carrying out Colours or Sunset) and taking charge in emergency situations in Damage Control Headquarters. Whilst the OOD may be outranked by more senior officers on board, he or she is technically only subordinate to the Captain and the Executive Officer whilst carrying out his or her duties, but a prudent junior officer always seeks advice. Generally on warships, the OOD will be a commissioned junior officer who holds a Harbour Watchkeeping Certificate. On shore establishments, Warrant Officers may be used to augment the duty roster.