agree vs concord

agree is not a noun while concord is a noun.

Word	Noun	Adjective	Verb	Adverb
agree	No	No	Yes	No
concord	Yes	No	Yes	No

As verbs, agree and concord are synonyms defined as:

Other synonyms of agree include concur, hold.

As verbs, concord is a hyponym of agree; that is, concord is a word with a more specific, narrower meaning than agree:

agree: be compatible, similar or consistent; coincide in their characteristics
concord: go together

As verbs, agree and concord are synonyms defined as:

Other synonyms of agree include accord, consort, fit in, harmonise, harmonize.

agree (noun)	concord (noun)
	agreement of opinions
	the determination of grammatical inflection on the basis of word relations
	a harmonious state of things in general and of their properties (as of colors and sounds); congruity of parts with one another and with the whole

agree (verb)	concord (verb)
be in accord; be in agreement	be in accord; be in agreement
consent or assent to a condition, or agree to do something	arrange the words of a text so as to create a concordance
achieve harmony of opinion, feeling, or purpose	arrange by concord or agreement
be agreeable or suitable	go together
be compatible, similar or consistent; coincide in their characteristics
go together
show grammatical agreement