Definition of reason in US English:



  • 1A cause, explanation, or justification for an action or event.

    ‘the minister resigned for personal reasons’
    ‘it is hard to know for the simple reason that few records survive’
    • ‘The simple reason is the people in charge of spending the money are not accountable to anyone.’
    • ‘I'm hoping to get an explanation or a reason for my not being involved.’
    • ‘With their unforced errors, they were the main reason for the goals against them.’
    • ‘Their goal is simply to cause terror without a justified reason.’
    • ‘He attributed the fine weather on the day as the main reason why so many people decided to go to the matches.’
    • ‘Therefore, only the tip of the iceberg is known and most of the reasons leading to the event are missed.’
    • ‘Experts said that a tight work schedule was the main reason causing the decrease in reading.’
    • ‘Across all income groups, at least one in three people said their main reason for moving was to get a bigger home.’
    • ‘Everyone needs a reason to justify getting up in the morning, and a wage doesn't really do it for most people.’
    • ‘Weather patterns are very complex, and the specific reason for any one event cannot be determined.’
    • ‘Stress and too much administration are cited as some of the main reasons for people wanting a change.’
    • ‘One reason why this event may reverberate is exactly that disconnect.’
    • ‘The foundation also showed that liking an area was the main reason why people did not live closer to their work.’
    • ‘His main reason for quitting was personal, he said, as he wanted to spend more time with his wife and two children.’
    • ‘The reason for the present event, according to their explanation, is immodest behavior.’
    • ‘Does he not realise that the main reason most people don't use the bus is that they are slow, inconvenient and inefficient?’
    • ‘I am sure that in weeks and months to come these families will realise what a good home this was, and the main reason was the people who owned it.’
    • ‘Cost did not come into it, except as a reason to justify inaction.’
    • ‘China is probably the main reason for the rising demand for coal.’
    • ‘Research in Bolton found that stress is the main reason why people take time off work.’
    cause, grounds, ground, basis, rationale
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    1. 1.1 Good or obvious cause to do something.
      ‘we have reason to celebrate’
      • ‘Rangers supporters will now believe it is possible for them to have reason to tickle these next Sunday.’
      • ‘They have reason to celebrate the largest number of Liberal seats since the 1920s.’
      • ‘York Volleyball Club have good reason to celebrate a memorable Millennium season both on and off the court.’
      • ‘Lucia Brennan has had much reason to celebrate her athletics achievements recently.’
      • ‘But Lindsay already has reason to celebrate with Danielle's continuing progress.’
      • ‘And those of us who are part of one or more of those peoples have every reason to celebrate it.’
      • ‘We have in Europe good reason for optimism about the possibilities for the future.’
      • ‘For this match South Africa named a squad of 14 for reason only the selectors understood.’
      • ‘Since this party were in power this was reason enough to keep them there.’
      • ‘Guys love watching girls kissing and with good reason, girls understand what a kiss can do done the right way.’
      • ‘I thought that before the World 100m final, and I see no reason to change my mind.’
      • ‘He did want to kill Natasha, but this was not enough reason for his mind to decide.’
      • ‘Just because someone knocks on your door, phones you or stops you in the street is not good enough reason to change your mind.’
      • ‘It was abundantly clear that maritime European powers now had good reason to look for a direct sea passage to the Indies.’
    2. 1.2Logic A premise of an argument in support of a belief, especially a minor premise when given after the conclusion.
      • ‘Also, the relation between the reason and the conclusion, as we say, is just a logical one.’
      • ‘For this reason, Premise 2 of Malcolm's version is questionable.’
      • ‘The premise clearly gives a good reason for the conclusion, but it is not completely conclusive.’
      • ‘A cogent argument is one whose structure is such that the premises provide good reasons for accepting the conclusion.’
      • ‘An argument is a form of reasoning whereby one gives a reason or reasons in support of some claim.’
  • 2The power of the mind to think, understand, and form judgments by a process of logic.

    ‘there is a close connection between reason and emotion’
    • ‘For the scientist who has lived by his faith in the power of reason, the story ends like a bad dream.’
    • ‘We must not believe that all opinion is ideology, that reason is only power, that there is no truth to prevail.’
    • ‘Men are marked off from other animals by possessing reason and the power of thought.’
    • ‘Therefore reason in the sense of a cause is always understood as something rational.’
    • ‘It is necessary to darken his moral and mental vision, and, as far as possible, to annihilate his power of reason.’
    • ‘It was a state of mind where reason appeared to turn in on itself; became warped.’
    • ‘This is why The King is coming along as I need to have a point of sanity and reason to refer back to.’
    • ‘The sound of what is being said is just as important as the words themselves in what is, in a sense, a dialogue between reason and emotions.’
    • ‘He believed that with his powers of reason and his faith he could master the world about him.’
    • ‘The exhibition of reason's power in these scenes has no peer in theatre.’
    • ‘To be condemned for the colour or creed you were born with, really defies reason or sanity.’
    • ‘Galileo would not absolve them from blame for resorting to power when reason went against them.’
    • ‘Life today is guided not by logic and reason but rather by emotion, fear and sentimentality.’
    • ‘It was abolished hundreds of years ago as sanity and reason won the argument against those who sanctioned it.’
    • ‘You can, and should, exercise your powers of reason: that's why God gave them to you.’
    • ‘He thinks and learns systematically and is drawn to using logic and reason to prove and understand his faith.’
    • ‘They wished to use science and reason to understand nature and solve social problems.’
    • ‘Nothing restores my faith in the simple power of reason better than the utterances of a man of God.’
    • ‘Fortunately my powers of reason have not been entirely overcome and obliterated by received wisdom.’
    • ‘Games like chess and cards are used to help develop logical thinking and reason.’
    rationality, logic, logical thought, scientific thinking, reasoning, thought, cognition
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    1. 2.1 What is right, practical, or possible; common sense.
      ‘people are willing, within reason, to pay for schooling’
      • ‘The looser you get it, typically the better it turns and the faster you can get it to go within reason.’
      • ‘I feel I am doing all I can within reason to take an active part in my republican/capitalist democracy.’
      • ‘Eat whatever you want within reason on Christmas Day, but on all the other days try and be sensible.’
      • ‘It is, accordingly clear that, within reason, any order that the court makes will not stifle the appeal.’
      • ‘The streets are public highways and people should be allowed to do as they please, within reason.’
      • ‘He knew how bored she had been and wanted to try to accommodate her, but within reason.’
      • ‘The size is pretty much irrelevant, as is the amount of water, within reason.’
      • ‘Poetry books are my substitute for chocolate so, within reason, I indulge myself without guilt.’
      • ‘The decision was later extended to include all draught beers although the size of the head had to be within reason.’
      • ‘You can take advantage of this by waiting until the last minute and - within reason - naming your price.’
      • ‘The county council has taken all our views on board and promised it will do its best to accommodate the wishes of the village within reason.’
      • ‘My parents realised I was genuinely interested in the acting and would let me watch anything, within reason.’
      • ‘Sweetening the pot within reason to keep it out of their hands does make sense.’
      • ‘If you ask him nicely, he will, within reason, give you a lift back to wherever you are staying.’
      • ‘I am a great believer that if you pay your money you can say what you want within reason and our supporters are both very patient and biased!’
      • ‘A citizen has only to act within reason rather than familiarise himself with the law as it applies to him in all areas of life.’
      • ‘Tell the men they are free to start any fires they wish, as long as it is within reason.’
      • ‘Within reason, that should be their right, and not denied them by the worst sort of mean-minded bureaucracy.’
      • ‘The best advice is to try to be sure at all times, within reason, that you know where your son is, and whom he is with.’
      • ‘Keep the number of pages or hours within reason, and don't be upset if a day slips by.’
      good sense, good judgement, common sense, sense, judgement, understanding, wisdom, sagacity
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    2. 2.2one's reason One's sanity.
      ‘she is in danger of losing her reason’
      • ‘He ought to acquiesce, using at the same time the utmost powers of his reason to promote its repeal.’
      • ‘I think he was more afraid of losing his reason than he was of losing his life.’
      • ‘It addresses the audience by distracting its reason and arousing its emotion.’
      • ‘Later, after regaining his reason, Quentin worries for Tracy's safety, but she assures him that all will be well.’
      sanity, mind, mental faculties, mental health, soundness of mind
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[no object]
  • 1Think, understand, and form judgments by a process of logic.

    ‘humans do not reason entirely from facts’
    • ‘We see no escape from the logic of the judge's reasoning and Mr Nicol could suggest none.’
    • ‘Steve's mistake was to fall back on the scientific reasoning he had honed over his career.’
    • ‘Essentially, the subject is a search for knowledge that can be gained through reasoning.’
    • ‘His plan had been foolproof, probably working with instinct as well as reasoning.’
    • ‘It is, in my judgment, difficult on the face of it to fault any of the inspector's reasoning.’
    • ‘Kalvin squinted his eyes at him, reasoning out what he said and finally had to agree.’
    • ‘The following case provides an example of the Court's reasoning in this context.’
    • ‘Can someone tell us what commonsense reasoning the highway officials are applying here?’
    • ‘Now philosophers tend to focus on reasoning at its most explicit and deliberate.’
    • ‘With mathematical reasoning we smooth out differences in our dealings with each other.’
    • ‘My instinctive response is that animals are not able either to reason or to explain how they feel about being owned.’
    • ‘I am reasoning by analogy and by reference to the extension of rights for humans.’
    • ‘Spats, he reasons, are part of the way the world works and the best way of dealing with them is to let them happen.’
    • ‘He can't say for sure himself, reasoning that he was a bit young at the time to recall.’
    • ‘We should also do more research to explain how experts reason in complex or atypical cases.’
    • ‘The British and French refused to buy it at any price, reasoning that it would be left behind anyway.’
    • ‘Dave's reasoning behind this identification is based on a bell recovered a few years ago.’
    • ‘Choices based on the most minute reasoning but lacking any desire are vacuous.’
    • ‘This time he may do it, reasoning that he has nothing to lose when his removal is the explicit aim of the war.’
    thinking, line of thought, train of thought, thought, thought process, logic, reason, rationality, analysis, interpretation, explanation, deduction, rationalization, argumentation
    think rationally, think logically, think straight, use one's mind, use one's common sense, use one's head, use one's brain, think things through, cogitate
    calculate, come to the conclusion, conclude, reckon, think, consider, be of the opinion, be of the view, judge, deduce, infer, surmise
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    1. 1.1reason something outwith object Find an answer to a problem by considering various possible solutions.
      • ‘I guess I always assumed as a child that if I was considerate of others and reasoned things out, people would do likewise to and for me.’
      • ‘For a minute my heart pounded, until I reasoned it out.’
      • ‘It was one of those things you would like to do, but when you reasoned it out, you couldn't do it.’
      • ‘Analysts reason it out thus: Indian consumers, while being price- and value-conscious, are also brand conscious.’
      • ‘I will think about it over and over, trying to reason it out.’
      • ‘He didn't jump to conclusions, he would reason things out.’
      • ‘There was only silence, so either he knew which clause it was, or had reasoned it out.’
      • ‘But… it seems as if we're all also willing to bury the hatchet, and to forgive each other, and to reason things out.’
      • ‘Turning my attention back to the room I've found myself in, my tired mind desperately tries to reason things out, coming up fairly short in the process.’
      • ‘‘You reasoned it out beautifully,’ I exclaimed, in unfeigned admiration.’
      work out, find an answer to, find an solution to, think through, come to a conclusion about, sort out, make sense of, get to the bottom of, puzzle out, solve
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    2. 1.2reason with Persuade (someone) with rational argument.
      ‘I tried to reason with her, but without success’
      • ‘Because I have learned the hard way, if you think someone is disruptive, reasoning with them is pointless, debating the issue is pointless.’
      • ‘There is no reasoning with these people and now we have had enough.’
      • ‘Instead she decided that she would reason with him, apologise to him, then persuade him to go to bed.’
      • ‘The kinfolk (including myself at times) would often take to reasoning with her (in addition to the tantalizing bouts of teasing) concerning this hairdo.’
      • ‘As Kathy becomes frustrated navigating the legal-aid channels, she tries reasoning with her directly.’
      • ‘Miguel blinked, appalled and overwhelmed before rationally reasoning with himself, as all mathematicians can.’
      • ‘They make decisions with rationality and reason with each other through dialogue.’
      • ‘These are good reasons for remonstrating with him, or reasoning with him, or persuading him, or entreating him, but not for compelling him, or visiting him with evil in case he do otherwise.’
      • ‘Rondow said he tried reasoning with the officers, telling them he would miss the start of his course if he couldn't get across the border - to no avail.’
      • ‘Having to reason with a human and persuade her by the subterfuge of logic was exasperating.’
      talk round, bring round, win round, persuade, coax, prevail on, convince
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The construction the reason why … has been objected to on the grounds that the subordinate clause should express a statement, using a that-clause, not imply a question with a why-clause: the reason (that) I decided not to phone, rather than the reason why I decided not to phone. The reason why has been called a redundancy to be avoided, but it is a mild one, and idiomatic. An objection is also made to the construction the reason … is because, as in the reason I didn't phone is because my mother has been ill. The objection is made on the grounds that either “because” or “the reason” is redundant; it is better to use the word that instead (the reason I didn't phone is that …) or rephrase altogether (I didn't phone because …). Nevertheless, both the above usages are well established and, although they may be inelegant, they are generally accepted in standard English


  • beyond (all) reason

    • To a foolishly excessive degree.

      ‘he indulged Andrew beyond all reason’
      • ‘Sometimes there is a pain sometimes beyond reason.’
      • ‘In a marketing sense, it's to create loyalty beyond reason.’
      • ‘The people of Milan would find it beyond reason that Scotland was prepared to consign its single opera company to a year of darkness for the sake of an extra £2m.’
      • ‘I really don't believe he's going to try to kill her, he's just a kid with issues, but he has frightened my daughter beyond reason and that alone makes me want make him pay for his behavior in some way.’
      • ‘And how it hopes to win an appeal is beyond reason.’
      • ‘And then I went from being upset about the whole episode to being angry beyond reason.’
      • ‘The most intractable disputes are sometimes beyond reason, rooted as they are in irrational hatreds, tribal loyalties or systematic brainwashing into murderous paranoia and hysteria.’
      • ‘The demands of the animal rights advocates are beyond reason to me.’
      • ‘The man's crime was, without doubt, terrible and beyond reason.’
      • ‘So when in doubt they created money out of thin air (which is where money does come from) to a degree beyond reason.’
  • by reason of

    • formal Because of.

      ‘persons who, by reason of age, are in need of care’
      • ‘The second phase is the defense saying she was insane and should get not guilty by reason of insanity.’
      • ‘In my judgment the Part 20 claim must fail by reason of what I have said in the preceding paragraph.’
      • ‘The mere fact that a person calls himself an expert does not entitle him to be believed or accepted by reason of that very fact.’
      • ‘I am discriminated against, and so are my parents, by reason of age on almost a daily basis.’
      • ‘But in this case there was the agreement and the demand arose by reason of that.’
      • ‘The children have suffered emotional harm by reason of all the matters set out above.’
      • ‘I would expect the defense to go that route, to plead not guilty by reason of insanity.’
      • ‘You have not established it by reason of what I have just been putting to you, so do not exaggerate, please.’
      • ‘So the chances for change and fundamental change by reason of exposure here are good.’
      • ‘What does it mean to say you are increasing a sentence by reason of or in consideration of evidence that was not given at the trial?’
      because of, on account of, as a result of, as a consequence of, owing to, due to, by virtue of, thanks to, through
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  • for some reason

    • Used to convey that one doesn't know the reason for a particular state of affairs, often with the implication that one finds it strange or surprising.

      ‘for some reason he likes you’
      • ‘I was not recognized for some reason or the other so that there was no way of stopping the bill.’
      • ‘Ok, so, none of my damn business, but I have always been curious about this for some reason.’
      • ‘She had two attempts on the left side, which for some reason never gets the same effect.’
      • ‘As the tide was rising, for some reason, a strong current was pulling us into the darkness.’
      • ‘I was looked on favourably by both for some reason and I knew people on both sides.’
      • ‘The first of these has, for some reason, gained ready acceptance among his followers.’
      • ‘It's a much easier joke to hear from a female friend than a male friend, for some reason.’
      • ‘He fumbled for the bedside clock to see what time it was: but for some reason couldn't find it.’
      • ‘Have the world's press somehow colluded to gang up against him, for some reason?’
      • ‘He didn't trust banks for some reason and kept all his money and gold in a stupid safe in the attic.’
  • listen to reason

    • Be persuaded to act sensibly.

      ‘the child is usually too emotionally overwrought to listen to reason’
      • ‘For the sake of Graham Rix, who is growing into this job after a difficult beginning, and his players, who have really warmed to their manager, you hope Romanov will now listen to reason.’
      • ‘First came the good news: the Prime Minister had listened to reason and postponed the local elections for a month.’
      • ‘I was in no state to listen to reason and we began to argue in the middle of the dancefloor.’
      • ‘You may think the influence of school will add another dimension to create a child who is self-controlled, listens to reason and generally presents very few problems.’
      • ‘I could so easily have been the thing responsible for pushing that girl over the edge, I was lucky, she took to me and was able to listen to reason.’
      • ‘No one listens to reason, everything is based on which way the winds of politics are blowing.’
      • ‘I realized that there was no way this guy was going to listen to reason, that nothing I could say was going to change his mind.’
      • ‘Mr. Roberts and his ilk may not listen to reason or polite discourse, but I'll bet they pay plenty of attention to the sound of falling ratings.’
      • ‘I should have listened to reason… to the quiet voice of experience warning me of the dangers inherent in my planned course of action.’
      • ‘It is not an argument that I accept, but I am ready to listen to reason.’
  • theirs (or ours) not to reason why

    • Used to suggest that it is not someone's (or someone else's) place to question a situation or system.

      • ‘In all likelihood they took on board the soldiers' dictum of ‘ours not to reason why’ and just got on with it.’
      • ‘Her lot is not to reason why.’
      • ‘Theirs not to make reply, theirs not to reason why, theirs but to do and die.’
      • ‘It all seems as unregal as it is legal, but ours is not to reason why.’
  • reason of state

    • A purely political reason for action on the part of a ruler or government, especially where a departure from openness, justice, or honesty is involved.

      ‘the king returned that he had reasons of state for all he did’
  • (it) stands to reason

    • It is obvious or logical.

      ‘it stands to reason that if you can eradicate the fear the nervousness will subside’
      • ‘IT stands to reason that if we want to tackle crime and corruption effectively, then we need to have the mechanisms, people and resources in place to deal with it.’
      • ‘It stands to reason that affordable homes are not going to be built in Nelson.’
      • ‘I suppose this stands to reason because a team good enough to win an All-Ireland doesn't become good overnight, it is a gradual process of improvement.’
      • ‘It stands to reason, and is logical, that if one digs something out of the ground such as coal and burns it and turns it into a different form, well, then it cannot be renewable.’
      • ‘It stands to reason, of course, that fluctuations in energy emitted by the sun would account, wholly or in part, for temperature variations on earth.’
      • ‘It stands to reason why experts maintain that nutrition contributes substantially in this respect because healthy skin tissues will have excellent elasticity.’
      • ‘How teachers teach is important, but it surely stands to reason that boys and girls need both male and female role models in their formative educational years.’
      • ‘It stands to reason therefore, that any problems that arise in the application of the idea of ‘free markets’ will cause problems in the application of the third way.’
      • ‘It stands to reason there will be colossal failures.’
      • ‘It stands to reason that we cannot expect Namibia to flourish economically if this is the predominant mindset at work among our politicians and in our civil service.’


Middle English: from Old French reisun (noun), raisoner (verb), from a variant of Latin ratio(n-), from the verb reri ‘consider’.