What does "cadet" mean?

Cadet: (Mil.) (a) A gentleman who carries arms in a regiment, as a volunteer, with a view of acquiring military skill and obtaining a commission. (b) A young man in training for military or naval service; esp. a pupil in a military or naval school, as at West Point, Annapolis, or Woolwich. Note: All the undergraduates at Annapolis are Naval cadets. The distinction between Cadet midshipmen and Cadet engineers was abolished by Act of Congress in 1882.