Possible target for repairing telephone problem (8)
I believe the answer is:
deadline
'problem' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for deadline that I've seen before include "Time-limit as for reporter's copy" , "Time-limit as for journalist's copy" , "last possible time" , "a writer may have to meet" , "Time by which task must be completed" .)