Crow that is revealing new recruit (6)
I believe the answer is:
rookie
'new recruit' is the definition.
(a rookie is a new recruit or trainee)
'crow that is' is the wordplay.
'crow' becomes 'rook' (I have seen 'Gregarious crow ' mean 'rook' so perhaps 'crow' could also mean 'rook').
'that is' becomes 'ie' (abbreviation for id est, 'that is' in Latin).
'rook'+'ie'='ROOKIE'
'revealing' is the link.
(Other definitions for rookie that I've seen before include "New recruit as to army" , "Novice" , "new team member" , "untrained soldier" , "Raw recruit" .)