"Semper Fi" soldier (6)
I believe the answer is:
marine
'semper fi soldier' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for marine that I've seen before include "Oceanic" , "Airmen (anag.)" , "'Nautical, maritime (6)'" , "Soldier serving on land and sea" , "jolly" .)