Oxford Advanced American Dictionary

Definition of reason noun from the Oxford Advanced Learner's Dictionary

Oxford3000

reason

noun
reason pronunciation English ˈriːzn reason pronunciation American ˈriːzn
 
1 [countable] a cause or an explanation for something that has happened or that somebody has donereason (why…) I'd like to know the reason why you're so late.Give me one good reason why I should help you.reason (that…) We aren't going for the simple reason that we can't afford it.reason (for something) She gave no reasons for her decision.reason (for doing something) I have no particular reason for doubting him.He said no but he didn't give a reason.For some reason (= one that I don't know or don't understand) we all have to come in early tomorrow.The man attacked me for no apparent reason.She resigned for personal reasons.For reasons of security the door is always kept locked.He wants to keep them all in his office for reasons best known to himself.people who, for whatever reason, are unable to support themselves‘Why do you want to know?’ ‘No reason(= I do not want to say why).‘Why did she do that?’ ‘She must have her reasons(= secret reasons which she does not want to tell). (formal) He was excused by reason of (= because of) his age.2 [uncountable] a fact that makes it right or fair to do somethingreason (to do something) They have reason to believe that he is lying.We have every reason (= have very good reasons) to feel optimistic.You have no reason to accuse him of laziness.reason (why…) There is no reason why we should agree to this.reason (for something/for doing something) This result gives us all the more reason for optimism.She complained, with reason (= rightly), that she had been underpaid.3 [uncountable] the power of the mind to think in a logical way, to understand and have opinions, etcOnly human beings are capable of reason (= of thinking in a logical way, etc.).to lose your reason (= become mentally ill)the conflict between faith and reason4 [uncountable] what is possible, practical or rightI can't get her to listen to reason.Why can't they see reason?to be open to reason (= to be willing to accept sensible advice)He's looking for a job and he's willing to do anything within reason.
Idioms

it stands to reason

(informal) it must be clear to any sensible person who thinks about itIt stands to reason that they'll leave if you don't pay them enough.
more at there's no rhyme or reason to/for somethingwithout rhyme or reason at rhyme nounUsage notesUsage note: reasonexplanation grounds basis excuse motive justification pretextThese are all words for a cause or an explanation for something that has happened or that somebody has done.reason a cause or an explanation for something that has happened or that somebody has done; a fact that makes it right or fair to do something: He said no but he didn't give a reason.explanation a statement, fact or situation that tells you why something has happened; a reason given for something: The most likely explanation is that his plane was delayed. She left the room abruptly without explanation.grounds (rather formal) a good or true reason for saying, doing or believing something: You have no grounds for complaint.basis (rather formal) the reason why people take a particular action: On what basis will this decision be made?excuse a reason, either true or invented, that you give to explain or defend your behaviour; a good reason that you give for doing something that you want to do for other reasons: Late again! What's your excuse this time? It gave me an excuse to take the car.motive a reason that explains somebody's behaviour: There seemed to be no motive for the murder.justification (rather formal) a good reason why something exists or is done: I can see no possible justification for any further tax increases.grounds or justification?Justification is used to talk about finding or understanding reasons for actions, or trying to explain why it is a good idea to do something. It is often used with words like little, no, some, every, without, and not any. Grounds is used more for talking about reasons that already exist, or that have already been decided, for example by law: moral/economic grounds.pretext (rather formal) a false reason that you give for doing something, usually something bad, in order to hide the real reason: He left the party early on the pretext of having to work.(a/an) reason/explanation/grounds/basis/excuse/motive/justification/pretext for somethingthe reason/motive behind somethingon the grounds/basis/pretext of/that…(a) good/valid reason/explanation/grounds/excuse/motive/justificationUsage notesUsage note: thereforeWays of saying ‘For this reason…’Today's children eat more junk food and get less exercise than previous generations of children. It is not surprising, therefore, that rates of childhood obesity are on the increase.Children who grow up on a diet of junk food find it difficult to change this habit later in life. It is essential, therefore, that parents encourage healthy eating from an early age.Children who grow up on a diet of junk food find it difficult to change this habit later in life. For this reason, /This is why it is essential that children eat healthily from an early age.Eating habits formed in childhood tend to continue into adult life. Thus, the best way to prevent heart disease among adults is to encourage healthy eating from an early age.Eating habits formed in childhood tend to continue into adult life, hence the importance of encouraging healthy eating from an early age. Language Banks at because of, cause, consequently, emphasis, vital