Revolutionary veterans need to conceal trap (7)
I believe the answer is:
ensnare
'trap' is the definition.
(to ensnare is to trap or capture)
'revolutionary veterans need to conceal' is the wordplay.
'revolutionary' says the letters should be written backwards (letters revolve around).
'to conceal' indicates a hidden word.
'eransne' is hidden within 'veterans need'.
'eransne' written backwards gives 'ENSNARE'.
(Other definitions for ensnare that I've seen before include "Ecstatic expression of feeling" , "Ambush" , "Catch as if in a trap or net" , "Capture, trap" .)