Engineers packing and getting back (9)
I believe the answer is:
restoring
'getting back' is the definition.
Although both the answer and definition are present participle verbs, I cannot see how they can define each other.
'engineers packing and' is the wordplay.
I cannot quite see how this works, but
'engineers' could be 'res' and 'res' is located in the answer.
'and' could be 'n' (common abbreviation for 'and') and 'n' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for restoring that I've seen before include "Bringing back to former state" , "Returning to the original state" .)