I'd learn about Emerald Isle (7)
I believe the answer is:
ireland
'emerald isle' is the definition.
(synonyms)
'i'd learn about' is the wordplay.
'about' is an anagram indicator.
'id'+'learn'='idlearn'
'idlearn' anagrammed gives 'IRELAND'.
(Other definitions for ireland that I've seen before include "British composer" , "music writer" , "Hibernia" , "State" , "An idler (anag)" .)