- a peninsula in S Europe, S of the Danube River and bordered by the Adriatic, Ionian, Aegean, and Black seas.
- a large peninsula in SE Europe, between the Adriatic and Aegean Seas
Peninsula in southeastern Europe between the Ionian Sea and Adriatic Sea on the west, the Mediterranean Sea on the south, and the Aegean Sea and Black Sea on the east. The nations of the Balkan Peninsula include Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Greece, Macedonia, Romania, Slovenia, and the former Yugoslavia. The European portion of Turkey is also on the Balkan Peninsula. (See also Balkanization.)