Isthmus of Darien vs Isthmus of Panama

Isthmus of Darien and Isthmus of Panama both are nouns.

Word	Noun	Adjective	Verb	Adverb
Isthmus of Darien	Yes	No	No	No
Isthmus of Panama	Yes	No	No	No

As nouns, Isthmus of Darien and Isthmus of Panama are synonyms defined as:

Isthmus of Darien and Isthmus of Panama: the isthmus that connects Central America and South America; was formerly called the Isthmus of Darien

Isthmus of Darien (noun)	Isthmus of Panama (noun)
the isthmus that connects Central America and South America; was formerly called the Isthmus of Darien	the isthmus that connects Central America and South America; was formerly called the Isthmus of Darien