concession vs agreement

concession and agreement both are nouns.

Word	Noun	Adjective	Verb	Adverb
concession	Yes	No	No	No
agreement	Yes	No	No	No

As nouns, agreement is a hypernym of concession; that is, agreement is a word with a broader meaning than concession:

concession (noun)	agreement (noun)
a contract granting the right to operate a subsidiary business	compatibility of observations
a point conceded or yielded	the thing arranged or agreed to
the act of conceding or yielding	the verbal act of agreeing
	the statement (oral or written) of an exchange of promises
	the determination of grammatical inflection on the basis of word relations
	harmony of people's opinions or actions or characters