Someone who has spent three years either at a university-and-approved-hospital(s) or (prior to the mid-late 90's) at a hospital school of nursing. The qualification of Registered Nurse admits them to the UK official register of nurses and permits them to practice. The training course also awards a university degree (previously, diploma of higher education).
Civilian nurse training comprises a common foundation course followed by specialisation and qualification in one of four branches: adult, child, mental health or mental handicap. Within the military, only the first two branches are offered.
Army nurses are members of the Queen Alexandra's Royal Army Nursing Corps aka QARANC
Navy nurses are members of Queens Alexandra's Royal Naval Nursing Service aka QARNNS
RAF nurses are members of Princess Mary's Royal Air Force Nursing Services aka PMRAFNS
As the old saying goes....'"there are two certainties in life..."'