Singan vs Changan

Singan and Changan both are nouns.

Word	Noun	Adjective	Verb	Adverb
Singan	Yes	No	No	No
Changan	Yes	No	No	No

As nouns, Singan and Changan are synonyms defined as:

Singan and Changan: a city of central China; capital of ancient Chinese empire 221-206 BC

Other synonyms of Singan include Hsian, Sian, Xi'an, Xian.

Singan (noun)	Changan (noun)
a city of central China; capital of ancient Chinese empire 221-206 BC	a city of central China; capital of ancient Chinese empire 221-206 BC