Charity acquires rebuilt store for future generations (9)
I believe the answer is:
posterity
'future generations' is the definition.
(I've seen this before)
'charity acquires rebuilt store' is the wordplay.
'charity' becomes 'pity' (pity can mean charitable behaviour).
'acquires' indicates putting letters inside.
'rebuilt' indicates anagramming the letters.
'store' with letters rearranged gives 'oster'.
'pity' going around 'oster' is 'POSTERITY'.
'for' acts as a link.
(Other definitions for posterity that I've seen before include "Succeeding generations" , "Future generations" , "for people coming later" .)