Noun (1): A feeling of wanting to know or learn more about something. "She has a keen interest in learning new languages."
Noun (2): A hobby or activity that you enjoy doing. "What are your main interests?"
Noun (3): Money paid to a lender for borrowing money, or received from a bank for saving money. "The mortgage carries a fixed interest rate of 4.5%."
Verb: To attract someone's curiosity or attention. "Does this subject interest you?"
What Does Interest Mean?
Interest is one of the most common words in English, appearing across everyday conversation, academic writing, and financial contexts. Its core sense — a feeling of curiosity directed towards something — is A2 level and learned early, while the financial meaning belongs to B2 and above.
The word works as both a noun and a verb without any change in spelling or pronunciation. As a noun it pairs with the preposition in: "an interest in science", "interested in history". As a verb it takes a direct object: "This film will interest you." Understanding this dual nature helps avoid the most common ESL errors with this word.
Two participial adjectives grow from the verb: interested (how a person feels) and interesting (a quality something possesses). Mastering the difference between these two forms is one of the most valuable intermediate grammar steps for English learners.
Etymology
The word interest traces back to the Latin verb interesse — literally "to be between" (inter = between + esse = to be) — which came to mean "to concern" or "to matter". In medieval Latin interesse became a noun denoting the compensation due for a loss, giving rise to the financial sense. The word entered English via Old French in the 15th century, initially referring exclusively to money owed on a debt. The broader meaning of "curiosity" or "engagement with something" developed in the 16th and 17th centuries as writers began using interest to describe what holds a person's attention. The same Latin root gives English the words interesting, interested, disinterested, and uninterested.
Example Sentences by CEFR Level
| Level | Sentence | Usage note |
|---|---|---|
| A2 | She has a keen interest in learning new languages. | noun + keen interest in |
| B1 | The teacher noticed that the students were losing interest in the topic. | lose interest in — common collocation |
| B1 | Does modern architecture interest you at all? | verb form — direct object |
| B2 | The bank pays 3.5% annual interest on instant-access savings accounts. | financial noun — uncountable |
| C1 | Several lobby groups with a vested interest in the outcome have challenged the proposed legislation. | vested interest — formal/legal register |
Collocations
| Collocation | Example | Register |
|---|---|---|
| take an interest in | He started to take an interest in photography last year. | general |
| show interest in | Several investors have shown interest in the start-up. | general / business |
| keen interest | She has always had a keen interest in environmental issues. | general |
| lose interest in | He lost interest in the project after the deadline changed. | general |
| express interest in | Three candidates expressed interest in the position. | formal |
| area of interest | What is your main area of interest? | academic / formal |
| common interest | We found we had a lot of common interests. | general |
| interest rate | The Bank of England raised the interest rate by 0.25%. | financial |
| compound interest | Compound interest means you earn interest on your interest. | financial |
| vested interest | The committee members have a vested interest in the decision. | formal / legal |
Usage Notes
Key Points for Learners
Always use "in" after interest (noun and adjective): "an interest in science", "interested in history". Using "to" or "about" is incorrect in standard British English.
Interested vs interesting: Use interested to describe how a person feels ("I am interested in jazz") and interesting to describe what causes that feeling ("Jazz is interesting"). This is the most common source of errors for learners at A2–B1.
Countable vs uncountable: Interest is uncountable in the general sense ("with great interest", "of no interest") but countable when referring to specific hobbies ("She has many interests"). The financial meaning is always uncountable.
Disinterested vs uninterested: These are not synonyms. Disinterested means impartial or without a personal stake in the outcome (formal/C1). Uninterested means not curious or bored. Confusing them is a common error even among native speakers.
Common Mistakes
Mistakes to Avoid
I am interesting in learning Spanish.
I am interested in learning Spanish. ('interested' describes how you feel; 'interesting' describes the topic itself)
She has interest to history.
She has an interest in history. (use the preposition 'in', not 'to'; add the article 'an')
What are your interests about?
What are your interests? ('interests' stands alone — no preposition is needed after it)
The bank pays me interests every month.
The bank pays me interest every month. (financial 'interest' is uncountable — never use the plural)