Arid; dried up (4)
I believe the answer is:
sere
I believe this is a double definition.
'arid' is the first definition.
(I've seen this in another clue)
'dried up' is the second definition.
(I've seen this before)
(Other definitions for sere that I've seen before include "Dry, withered" , "'Dried-up, shrivelled (4)'" , "Erse (anag.); withered (literary)" , "Dried up, withered" .)