Wreck new store in outskirts of Derby (7)
I believe the answer is:
destroy
'wreck' is the definition.
(I've seen this before)
'new store in outskirts of derby' is the wordplay.
'new' indicates an anagram.
'in' is an insertion indicator.
'outskirts of' means to remove the middle letters.
'derby' with its centre removed is 'dy'.
'store' with letters rearranged gives 'estro'.
'estro' placed within 'dy' is 'DESTROY'.
(Other definitions for destroy that I've seen before include "'Demolish, ruin (7)'" , "Ruin; pull down" , "Get rid of" , "Kill; ruin" , "Demolish; pull down" .)