Sion vs Jerusalem

Sion and Jerusalem both are nouns.

Word	Noun	Adjective	Verb	Adverb
Sion	Yes	No	No	No
Jerusalem	Yes	No	No	No

Sion (noun)	Jerusalem (noun)
an imaginary place considered to be perfect or ideal	capital and largest city of the modern state of Israel (although its status as capital is disputed); it was captured from Jordan in 1967 in the Six Day War; a holy city for Jews and Christians and Muslims; was the capital of an ancient kingdom
Jewish republic in southwestern Asia at eastern end of Mediterranean; formerly part of Palestine
originally a stronghold captured by David (the 2nd king of the Israelites); above it was built a temple and later the name extended to the whole hill; finally it became a synonym for the city of Jerusalem