Large peninsula in southeastern Europe (6)
I believe the answer is:
balkan
'large peninsula in southeastern europe' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for balkan that I've seen before include "As Kosovo, Albania, etc" , "The -- peninsula contains Greece, Albania, etc" , "Large peninsula in southeastern Europe" , "Of SE European area" , "Such as Serbia, Kosovo" .)