business vs concern

business and concern both are nouns.

Word	Noun	Adjective	Verb	Adverb
business	Yes	No	No	No
concern	Yes	No	Yes	No

As nouns, concern is a hypernym of business; that is, concern is a word with a broader meaning than business:

Other hypernyms of business include headache, vexation, worry.

As nouns, business and concern are synonyms defined as:

business and concern: a commercial or industrial enterprise and the people who constitute it

Other synonyms of business include business concern, business organisation, business organization.

business (noun)	concern (noun)
the principal activity in your life that you do to earn money	something that interests you because it is important or affects you
the activity of providing goods and services involving financial and commercial and industrial aspects	something or someone that causes anxiety; a source of unhappiness
the volume of commercial activity	a feeling of sympathy for someone or something
incidental activity performed by an actor for dramatic effect	an anxious feeling
an immediate objective	a commercial or industrial enterprise and the people who constitute it
a rightful concern or responsibility
a commercial or industrial enterprise and the people who constitute it
customers collectively
business concerns collectively

business (verb)	concern (verb)
	be relevant to
	be on the mind of