Arid sort of attack (4)
I believe the answer is:
raid
'attack' is the definition.
(I know that raid is a type of attack)
'arid sort' is the wordplay.
'sort' indicates an anagram.
'arid' with letters rearranged gives 'RAID'.
'of' is the link.
(Other definitions for raid that I've seen before include "Finch and Bronson starred in . . . . On Entebbe" , "Stock Exchange activity" , "Sally" , "Invade" , "Smash-and-grab?" .)