Breakdown out in Iran, possibly (9)
I believe the answer is:
ruination
'breakdown' is the definition.
(thesaurus)
'out in iran possibly' is the wordplay.
'possibly' indicates an anagram.
'out'+'in'+'iran'='outiniran'
'outiniran' anagrammed gives 'RUINATION'.
(Other definitions for ruination that I've seen before include "bankruptcy" , "Crippling defeat" , "Complete downfall" , "total disaster" , "Complete destruction or collapse" .)