Changjiang vs Yangtze River

Changjiang and Yangtze River both are nouns.

Word	Noun	Adjective	Verb	Adverb
Changjiang	Yes	No	No	No
Yangtze River	Yes	No	No	No

As nouns, Changjiang and Yangtze River are synonyms defined as:

Changjiang and Yangtze River: the longest river of Asia; flows eastward from Tibet into the East China Sea near Shanghai

Other synonyms of Changjiang include Chang, Chang Jiang, Yangtze, Yangtze Kiang.

Changjiang (noun)	Yangtze River (noun)
the longest river of Asia; flows eastward from Tibet into the East China Sea near Shanghai	the longest river of Asia; flows eastward from Tibet into the East China Sea near Shanghai