French article put in after secrecy (7)
I believe the answer is:
silence
'secrecy' is the definition.
(I know that secrecy can be written as silence)
'french article put in after' is the wordplay.
'french article' becomes 'le' (definite article in French).
'put in' means one lot of letters goes inside another.
'after' becomes 'since' (since can mean after a certain time).
'le' inserted within 'since' is 'SILENCE'.
(Other definitions for silence that I've seen before include "Secrecy; stillness" , "Soundlessness" , "No talking" , "'The rest is - - '(Hamlet)" , "Quietude" .)