1 a : a feeling of wanting to learn more about something or to be involved in something [noncount] ▪ She told us about her lifelong interest in music. ▪ I have no interest in politics. [=I am not interested in politics] ▪ The kids listened to the speaker for a little while, but then lost interest. ▪ The speaker wasn't able to hold/keep their interest. ▪ I've been following his career with (great) interest. [singular] ▪ She took/had an active interest in the political debate. ▪ He expressed/showed an interest in learning more about photography.
b [noncount] : a quality that attracts your attention and makes you want to learn more about something or to be involved in something
▪ The stories about his personal life add interest to the book. ▪ He looked through the available magazines, but found nothing of interest. [=nothing interesting] ▪ I thought this article might be of interest to you. ▪ We visited many places of interest on our vacation. ▪ The price of the ticket was a matter of interest to everyone. ▪ a story that has human interest = a human-interest story [=a story that is interesting because it involves the experiences of real people] 2 [count] : something (such as a hobby) that a person enjoys learning about or doing
▪ Music is one of her many interests. ▪ She has a number of outside interests. [=things that she enjoys doing when she is not working] 3 [count] — used when discussing what is the best or most helpful thing for someone ▪ It's in your (own) interest to keep silent. ▪ The judge decided that it would be in the (best) interests of the child to continue living with her mother. ▪ If he refuses to cooperate, he'll be acting against his own interests. [=he'll be acting in a way that is harmful to himself] ▪ a policy that is not in the national/public interest [=that is more likely to harm than to help the nation/public] ▪ The law is intended to protect/safeguard the interests of people who have no health insurance. ▪ He claims that he has her (best) interests at heart. [=that he is concerned about her and wants to help her] ▪ In the interest of [=for the sake of] fairness, we decided to get everyone's opinion before making a decision. 4 [noncount] a : the money paid by a borrower for the use of borrowed money
▪ We pay six percent interest on the loan. ▪ The loan was repaid with interest. ▪ monthly interest payments/charges ▪ interest rates ▪ an interest-free loan [=a loan that the borrower does not have to pay any interest on]
b : money paid to you by a bank for the money you have in a bank account
▪ He made about $500 in interest last year. — see also compound interest, simple interest 5 [count] : a legal share in a business or property
▪ They offered to buy out his interest in the company. 6 interests [plural] : a group financially involved in an industry or business
▪ This law is opposed by the oil interests.