Peloponnese vs Peloponnesian Peninsula

Peloponnese and Peloponnesian Peninsula both are nouns.

Word	Noun	Adjective	Verb	Adverb
Peloponnese	Yes	No	No	No
Peloponnesian Peninsula	Yes	No	No	No

As nouns, Peloponnese and Peloponnesian Peninsula are synonyms defined as:

Peloponnese and Peloponnesian Peninsula: the southern peninsula of Greece; dominated by Sparta until the 4th century BC

Other synonyms of Peloponnese include Peloponnesus.

Peloponnese (noun)	Peloponnesian Peninsula (noun)
the southern peninsula of Greece; dominated by Sparta until the 4th century BC	the southern peninsula of Greece; dominated by Sparta until the 4th century BC