Save from a terrible curse at closing time (6)
I believe the answer is:
rescue
'save' is the definition.
(rescuing is a kind of saving)
'a terrible curse at closing time' is the wordplay.
'a terrible' indicates anagramming the letters.
'at' says to put letters next to each other.
'closing time' becomes 'e' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'curse' anagrammed gives 'rescu'.
'rescu'+'e'='RESCUE'
'from' is the link.
Can you help me to learn more?
(Other definitions for rescue that I've seen before include "Free from danger or captivity" , "liberation" , "Save from danger or distress" , "Retrieve" , "Free - recovery" .)