Gershwin opening nursery in Islamic republic? (4)
I believe the answer is:
iran
'islamic republic?' is the definition.
(I've seen this before)
'gershwin opening nursery' is the wordplay.
'gershwin' becomes 'ira' (lyricist Ira Gershwin, brother of George).
'opening' suggests taking the first letters.
The first letter of 'nursery' is 'n'.
'ira'+'n'='IRAN'
'in' is the link.
(Other definitions for iran that I've seen before include "Persia some time ago" , "Modern name for Persia" , "Persia today" , "Country where the official language is Farsi" , "Middle East Islamic republic" .)