A French dream - strangely defenceless (7)
I believe the answer is:
unarmed
'defenceless' is the definition.
(not carrying a weapon)
'a french dream strangely' is the wordplay.
'a french' becomes 'un' ('a' in French).
'strangely' indicates anagramming the letters.
'dream' with letters rearranged gives 'armed'.
'un'+'armed'='UNARMED'
(Other definitions for unarmed that I've seen before include "Like Venus de Milo" , "Not carrying a weapon" , "Weaponless" , "Not bearing a weapon" , "Lacking weapons" .)