Being a lush country with no king after one fails (9)

'being a lush' is the definition.
(obsession with wine - lush can mean a drunk)

'country with no king after one fails' is the wordplay.
'country' becomes 'oman' (Oman is an example).
'with no king' becomes 'ia' (I am not sure about this - if you are sure you should believe this answer much more).
'after' says to put letters next to each other.
'fails' is an anagram indicator (a failed spelling).
'one' with letters rearranged gives 'oen'.
'oman'+'ia'='omania'
'omania' after 'oen' is 'OENOMANIA'.