Military area needs rest CO ordered (6)
I believe the answer is:
sector
'military area' is the definition.
(I've seen this in another clue)
'rest co ordered' is the wordplay.
'ordered' indicates anagramming the letters.
'rest'+'co'='restco'
'restco' anagrammed gives 'SECTOR'.
'needs' is the link.
(Other definitions for sector that I've seen before include "A body of people who form part of society or economy" , "Corset (anag) - part of a circle" , "Division of a nation's economy" , "Distinct part of an economy; area for military operations" , ""Slice" cut from centre of circle" .)