a. A state of curiosity or concern about or attention to something: an interest in sports.
b. Something, such as a quality, subject, or activity, that evokes this mental state: counts the theater among his interests.
2. Regard for ones own benefit or advantage; self-interest. Often used in the plural: It is in your best interest to cooperate. She kept her own interests in mind.
3.
a. A right, claim, or legal share: an interest in the new company.
b. Something in which such a right, claim, or share is held: has interests overseas.
c. A person or group of persons holding such a right, claim, or share: a petroleum interest.
4. Involvement with or participation in something: She has an interest in the quality of her education.
5.
a. A charge for a loan, usually a percentage of the amount loaned.
b. An excess or bonus beyond what is expected or due.
6.
a. An interest group.
b. The particular cause supported by an interest group.
tr.v.in·ter·est·ed, in·ter·est·ing, in·ter·ests
1. To arouse the curiosity or hold the attention of: Your opinions interest me.
2. To cause to become involved or concerned with: tried to interest her in taking a walk.
3. Obsolete To concern or affect.
Idiom:
in the interest/interestsof
To the advantage of; for the sake of: thinking in the interest of the whole family; ate breakfast on the train in the interest of time.
[Middle English, from Old French, from Latin, it is of importance, third person sing. present tense of interesse, to be between, take part in : inter-, inter- + esse, to be; see es- in Indo-European roots.]
interest /ntrst, trst, trst/ n.1 [C;U] s.t. one wants to know more about, curiosity: I have an interest in learning about computers.2 [C;U] an activity or thing that one likes: He plays the piano well; it has become a real interest for him.3 [U] right to know: She is my daughter, so I have an interest in where she goes to college.4 [U] a percentage paid on an amount of money: The bank paid me 3% on my savings of $100, so I made $3 in interest.5 [C;U] financial relationship, part ownership: Along with several other families, they have an interest in an ice-cream shop and a bakery. v. [T] to make s.o. curious, attract s.o.s attention: Does chemistry interest you, or do you prefer biology?
Thesaurus: interest n.1 a desire (to learn), curiosity (about learning), passion for. Ant. a disinterest. 2 a pastime, hobby, pursuit 3 a concern 5 a share, percentage, stake. v. to appeal to s.o., intrigue s.o., hold s.o.s attention.
ntr
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st/ n. 1 [C;U] s.t. one wants to know more about, curiosity: I have an interest in learning about computers. 2 [C;U] an activity or thing that one likes: He plays the piano well; it has become a real interest for him. 3 [U] right to know: She is my daughter, so I have an interest in where she goes to college. 4 [U] a percentage paid on an amount of money: The bank paid me 3% on my savings of $100, so I made $3 in interest. 5 [C;U] financial relationship, part ownership: Along with several other families, they have an interest in an ice-cream shop and a bakery. 
v. [T] to make s.o. curious, attract s.o.s attention: Does chemistry interest you, or do you prefer biology?
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