A bit screwed back, now enabled again (4)
I believe the answer is:
anew
'again' is the definition.
(synonyms)
'a bit screwed back now enabled' is the wordplay.
I cannot really understand how this works, but
'a' could be 'an' and 'an' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for anew that I've seen before include "Once more (poetic)" , "From the beginning again" , "Again but differently" , "Afresh" , "Wane in a different way, again" .)