Poetic island's tavern is empty (9)
I believe the answer is:
innisfree
'poetic island's' is the definition.
'innisfree' can be an answer for 'island's' (Irish island). I also know that 'poetic' relates to this answer.
'tavern is empty' is the wordplay.
'tavern' becomes 'inn' (I've seen this before).
'empty' becomes 'free' (e.g. toilet, shower etc.).
'inn'+'is'+'free'='INNISFREE'
(Other definitions for innisfree that I've seen before include "` `I will arise and go now / and go to .........' ' (Yeats)" , "Island" , "The Lake Isle of --, (W. B. Yeats)" .)