Battle of Hampton Roads vs American Civil War

Battle of Hampton Roads and American Civil War both are nouns.

Word	Noun	Adjective	Verb	Adverb
Battle of Hampton Roads	Yes	No	No	No
American Civil War	Yes	No	No	No

Battle of Hampton Roads (noun)	American Civil War (noun)
a naval battle of the American Civil War (1862); the indecisive battle between the Monitor and the Merrimac	civil war in the United States between the North and the South; 1861-1865