Old soldier or cadet transferred (7)
I believe the answer is:
redcoat
'old soldier' is the definition.
(I've seen this before)
'or cadet transferred' is the wordplay.
'transferred' is an anagram indicator (I've seen 'transferring' mean this).
'or'+'cadet'='orcadet'
'orcadet' with letters rearranged gives 'REDCOAT'.
(Other definitions for redcoat that I've seen before include "British soldier (historical)" , "Tommy, once" , "Old-time British soldier" , "One employed to entertain" , "Old British soldier - Butlin's entertainment organiser" .)