Definition of “business” - Learner’s Dictionary

business

noun uk us /ˈbɪznɪs/
TRADE [ U ]

A1 the buying and selling of goods or services:

The shop closed last year, but now they're back in business.
We do a lot of business with China.
His company has gone out of business (= failed).
ORGANIZATION [ C ]

A2 an organization that sells goods or services:

My uncle runs a small decorating business.
WORK [ U ]

B1 work that you do to earn money:

She's in Vienna on business (= working).
a nasty/strange, etc business
be sb's (own) business

to be something private that other people do not need to know:

What he does in his own home is his business.
be none of sb's business

B2 If something is none of someone's business, they do not need to know about it, although they want to, because it does not affect them.

mind your own business

used to tell someone in a rude way that you do not want them to ask about something private

→ See also big business , show business

(Definition of “business” from the Cambridge Learner's Dictionary © Cambridge University Press)