Latest war over the sea (4,5)
I believe the answer is:
salt water
'the sea' is the definition.
(thesaurus)
'latest war over' is the wordplay.
'over' is an anagram indicator.
'latest'+'war'='latestwar'
'latestwar' is an anagram of 'SALT-WATER'.
(Other definitions for salt water that I've seen before include "part of recipe for boiled potatoes?" , "Of or living in the sea, related to saline content" , "Walter sat in brine" , "briny" , "Tears" .)