Cadet officer

Common military ranks in English
Navies	Armies	Air forces
Commissioned and Non-commissioned officers
Admiral of the fleet	Marshal or Field marshal	Marshal of the air force
Admiral	General	Air chief marshal
Vice admiral	Lieutenant general	Air marshal
Rear admiral	Major general	Air vice-marshal
Commodore	Brigadier or Brigadier general	Air commodore
Captain	Colonel	Group captain
Commander	Lieutenant colonel	Wing commander
Lieutenant commander	Major or Commandant	Squadron leader
Lieutenant	Captain	Flight lieutenant
Sub-lieutenant	Lieutenant or First lieutenant	Flying officer
Ensign	Second lieutenant	Pilot officer
Midshipman	Officer cadet	Flight cadet
Enlisted grades
Warrant officer or Chief petty officer	Warrant officer or Sergeant major	Warrant officer
Petty officer	Sergeant	Sergeant
Leading seaman	Corporal	Corporal
Seaman	Private	Aircraftman

Officer Cadet is a rank held by military cadets during their training to become commissioned officers. In the United Kingdom, the rank is also used by members of University Royal Naval Units, University Officer Training Corps and University Air Squadron however these are not trainee officers and most do not join the armed forces.

The term officer trainee is used interchangeably in some countries.

The Australian Defence Force follows the same usage as the British military system, using the rank of officer cadet (for the Australian Army (OCDT) and the Royal Australian Air Force (OFFCDT)), for personnel undergoing initial officer training. Unlike midshipmen in the Royal Australian Navy and officer cadets in the Royal Australian Air Force, who both hold a commission, officer cadets in the Australian Army do not yet hold a permanent commission, and are not saluted or referred to as "sir" or "ma'am". They do however hold probationary commissions. Officer cadets in the Australian Army are subordinate to warrant officers and officers and address them as "sir" or "ma'am". As officer cadets are appointed to their positions, they are technically superior to some other ranks, although they will typically not have direct subordinates.

Initial officer training can occur through either single-service institutions, such as the Royal Military College, Duntroon, Royal Australian Naval College, or the Officer Training School RAAF, or through the tri-service Australian Defence Force Academy. The ranks of officer cadet, staff cadet, and midshipman are primarily found at these establishments. However, RAAF officer trainees are often appointed to a higher rank while undergoing their initial training course at OTS if they have prior military experience, either as officer cadets prior to their initial officer course, or at airman rank. Officer cadets are also appointed to the Australian Army Reserve where training is conducted on a part-time basis at various University Regiments around the country.

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