ally vs friend

ally and friend both are nouns.

Word	Noun	Adjective	Verb	Adverb
ally	Yes	No	Yes	No
friend	Yes	No	No	No

As nouns, ally and friend are synonyms defined as:

ally (noun)	friend (noun)
a friendly nation	a person you know well and regard with affection and trust
an associate who provides cooperation or assistance	a person with whom you are acquainted
	an associate who provides cooperation or assistance
	a person who backs a politician or a team etc.

ally (verb)	friend (verb)
become an ally or associate, as by a treaty or marriage