blend in vs concord

blend in is not a noun while concord is a noun.

Word	Noun	Adjective	Verb	Adverb
blend in	No	No	Yes	No
concord	Yes	No	Yes	No

As verbs, concord is a hypernym of blend in; that is, concord is a word with a broader meaning than blend in:

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

blend in (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

blend in (verb)	concord (verb)
cause (something) to be mixed with (something else)	be in accord; be in agreement
blend or harmonize	arrange the words of a text so as to create a concordance
	arrange by concord or agreement
	go together