Allies vs alliance

Allies and alliance both are nouns.

Word	Noun	Adjective	Verb	Adverb
Allies	Yes	No	No	No
alliance	Yes	No	No	No

As nouns, alliance is a hypernym of Allies; that is, alliance is a word with a broader meaning than Allies:

Allies: in World War I the alliance of Great Britain and France and Russia and all the other nations that became allied with them in opposing the Central Powers
alliance: an organization of people (or countries) involved in a pact or treaty

Other hypernyms of Allies include alignment, alinement, coalition.

As nouns, alliance is a hypernym of Allies; that is, alliance is a word with a broader meaning than Allies:

Allies: the alliance of nations that fought the Axis in World War II and which (with subsequent additions) signed the charter of the United Nations in 1945
alliance: an organization of people (or countries) involved in a pact or treaty

Other hypernyms of Allies include alignment, alinement, coalition.

Allies (noun)	alliance (noun)
in World War I the alliance of Great Britain and France and Russia and all the other nations that became allied with them in opposing the Central Powers	the act of forming an alliance or confederation
the alliance of nations that fought the Axis in World War II and which (with subsequent additions) signed the charter of the United Nations in 1945	a formal agreement establishing an association or alliance between nations or other groups to achieve a particular aim
	an organization of people (or countries) involved in a pact or treaty
	a connection based on kinship or marriage or common interest
	the state of being allied or confederated