Southern writer the French put in irons (7)
I believe the answer is:
shackle
'put in irons' is the definition.
(I've seen this before)
'southern writer the french' is the wordplay.
'southern' becomes 's' (abbreviation).
'writer' becomes 'hack' (hack is a kind of writer**).
'the french' becomes 'le'.
's'+'hack'+'le'='SHACKLE'
(Other definitions for shackle that I've seen before include "Pair of fetters" , "Restrict" , "Put in irons" , "Restrain, limit" , "Chain with fetters" .)