Opted to construct store (5)
I believe the answer is:
depot
'store' is the definition.
(I know this)
'opted to construct' is the wordplay.
'to construct' is an anagram indicator.
'opted' is an anagram of 'DEPOT'.
(Other definitions for depot that I've seen before include "storeroom" , "Storehouse or terminus" , "Storehouse as for supplies" , "Storehouse or main bus station (5)" , "Bus garage" .)