Military trainee (5)
I believe the answer is:
cadet
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">military trainee</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for cadet that I've seen before include "One taking instructions" , "Trainee soldier" , "Officer-trainee" , "Young trainee, eg in the police" , "officer of the future" .)