rational


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Related to rational: rational function

ra·tion·al

 (răsh′ə-nəl)
adj.
1. Having or exercising the ability to reason. See Synonyms at logical.
2. Consistent with or based on reason or good judgment; logical or sensible: rational decisions.
3. Of sound mind; sane: wondered if the eccentric neighbor was not completely rational.
4. Mathematics Capable of being expressed as a quotient of integers.
n. Mathematics
A rational number.

[Middle English racional, from Old French racionel, from Latin ratiōnālis, from ratiō, ratiōn-, reason; see reason.]

ra′tion·al·ly adv.
ra′tion·al·ness n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

rational

(ˈræʃənəl)
adj
1. using reason or logic in thinking out a problem
2. in accordance with the principles of logic or reason; reasonable
3. of sound mind; sane: the patient seemed quite rational.
4. endowed with the capacity to reason; capable of logical thought: man is a rational being.
5. (Mathematics) maths expressible as a ratio of two integers or polynomials: a rational number; a rational function.
n
(Mathematics) maths a rational number
[C14: from Latin ratiōnālis, from ratiō reason]
ˈrationally adv
ˈrationalness n
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

ra•tion•al

(ˈræʃ ə nl, ˈræʃ nl)

adj.
1. based on or agreeable to reason: a rational decision.
2. exercising reason: a rational negotiator.
3. sane; lucid: The patient seems rational.
4. Math.
a. capable of being expressed exactly by a ratio of two integers.
b. (of a function) capable of being expressed exactly by a ratio of two polynomials.
n.
[1350–1400; Middle English racional < Latin ratiōnālis=ratiōn- (s. of ratiō) reason + -ālis -al1]
ra′tion•al•ly, adv.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

reasonable

rational
1. 'reasonable'

When someone is reasonable, they behave in a fair and sensible way.

Our mother was always very reasonable.
I can't do that, Morris. Be reasonable.

If something such as a proposal or judgement is reasonable, it is acceptable because it is fair or sensible.

Rules and procedures need to be accepted as reasonable by those who operate them.
There was no reasonable explanation for her decision.
2. 'rational'

You say that someone is rational when they are able to think clearly and make decisions and judgements based on reason rather than emotion.

Let's talk about this like two rational people.

You can also describe people's behaviour as rational.

This was a totally rational response to a set of complex problems.
Collins COBUILD English Usage © HarperCollins Publishers 1992, 2004, 2011, 2012
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.rational - an integer or a fraction
real, real number - any rational or irrational number
fraction - the quotient of two rational numbers
Adj.1.rational - consistent with or based on or using reason; "rational behavior"; "a process of rational inference"; "rational thought"
logical - capable of or reflecting the capability for correct and valid reasoning; "a logical mind"
reasonable, sensible - showing reason or sound judgment; "a sensible choice"; "a sensible person"
sane - mentally healthy; free from mental disorder; "appears to be completely sane"
irrational - not consistent with or using reason; "irrational fears"; "irrational animals"
2.rational - of or associated with or requiring the use of the mind; "intellectual problems"; "the triumph of the rational over the animal side of man"
mental - involving the mind or an intellectual process; "mental images of happy times"; "mental calculations"; "in a terrible mental state"; "mental suffering"; "free from mental defects"
3.rational - capable of being expressed as a quotient of integers; "rational numbers"
math, mathematics, maths - a science (or group of related sciences) dealing with the logic of quantity and shape and arrangement
irrational - real but not expressible as the quotient of two integers; "irrational numbers"
4.rational - having its source in or being guided by the intellect (as distinguished from experience or emotion); "a rational analysis"
intellectual - appealing to or using the intellect; "satire is an intellectual weapon"; "intellectual workers engaged in creative literary or artistic or scientific labor"; "has tremendous intellectual sympathy for oppressed people"; "coldly intellectual"; "sort of the intellectual type"; "intellectual literature"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.

rational

adjective
2. reasoning, thinking, cognitive, cerebral, ratiocinative Man, as a rational being, may act against his impulses.
3. sane, balanced, normal, all there (informal), lucid, of sound mind, compos mentis (Latin), in your right mind Rachel looked calmer and more rational now.
sane unreasonable, insane, irrational, unsound
Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition. 2002 © HarperCollins Publishers 1995, 2002

rational

adjective
1. Able to reason validly:
2. Possessing, proceeding from, or exhibiting good judgment and prudence:
3. Mentally healthy:
Idioms: all there, in one's right mind, of sound mind .
4. Consistent with reason and intellect:
The American Heritage® Roget's Thesaurus. Copyright © 2013, 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Translations
عاقِل، قادِر على التَّفْكيرعَقْلانِيّمَعْقول، مَنْطِقي
racionálnírozumnýrozumový
rationelfornuftig
järkeväjärkiperäinenrationaalinenjärjellinenjärkeenkäypä
racionalanrazboritrazuman
ésszerűracionális
skynsamlegurskynsamur; vitsmuna-
理にかなった
합리적인
protaujantisracionaliairacionalumasracionalus
domājošsloģiskssaprātīgs
rationell
ซึ่งมีเหตุผล
hợp lý

rational

[ˈræʃənl]
A. ADJ
1. (= logical) [argument, explanation] → racional, lógico
the rational thing to do would be tolo lógico or racional sería ...
2. (= reasonable) → razonable
let's be rational about thisseamos razonables
3. (= sane) [person] → sensato, cuerdo
he seemed quite rationalparecía estar perfectamente sensato or cuerdo
B. CPD rational number N (Math) → número m racional
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005

rational

[ˈræʃənəl] adj
[person] → rationnel(le)
[decision, explanation, argument] → rationnel(le); [solution] → rationnel(le); [thought, thinking, mind, reasoning] → rationnel(le)
(PSYCHOLOGY, PSYCHIATRY) (= of sound mind) → lucide
Collins English/French Electronic Resource. © HarperCollins Publishers 2005

rational

adj
(= having reason) creature, personvernunftbegabt, rational
(= sensible, reasonable) person, action, thinkingvernünftig, rational; activity, solutionvernünftig, sinnvoll; (Med: = lucid, sane) personbei klarem Verstand; it was the only rational thing to does war das einzig Vernünftige
(Math) → rational
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007

rational

[ˈræʃənl] adj (being) → razionale (Med) (lucid) → lucido/a; (faculty, action, argument) → razionale; (solution, explanation, reasoning) → logico/a, razionale
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995

rational

(ˈraʃənl) adjective
1. able to think, reason and judge etc. Man is a rational animal.
2. sensible; reasonable; logical; not (over-) influenced by emotions etc. There must be a rational explanation for those strange noises
ˈrationally adverb
ˌrationˈality noun
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.

rational

عَقْلانِيّ racionální rationel vernünftig έλλογος racional järkevä rationnel racionalan razionale 理にかなった 합리적인 rationeel rasjonell rozsądny racional рациональный rationell ซึ่งมีเหตุผล akıllıca hợp lý 理性的
Multilingual Translator © HarperCollins Publishers 2009

ra·tion·al

a. racional, cuerdo-a, basado-a en la razón.
English-Spanish Medical Dictionary © Farlex 2012
References in classic literature ?
Do you call that a rational system?" said the landowner, obviously rather proud of the word "rational."
Steadily as she persisted in taking the rational view, nevertheless the writing frightened her.
(for so I shall henceforth call him), and his children, and every servant of his house, were desirous to teach me; for they looked upon it as a prodigy, that a brute animal should discover such marks of a rational creature.
You see, gentlemen, reason is an excellent thing, there's no disputing that, but reason is nothing but reason and satisfies only the rational side of man's nature, while will is a manifestation of the whole life, that is, of the whole human life including reason and all the impulses.
To Bolkonski so many people appeared contemptible and insignificant creatures, and he so longed to find in someone the living ideal of that perfection toward which he strove, that he readily believed that in Speranski he had found this ideal of a perfectly rational and virtuous man.
I am bewildered in my endeavours to form some rational conjecture of what Mrs.
I wanted to try and think out how it was that rational or even half-rational men could ever have learned to wear armor, considering its incon- veniences; and how they had managed to keep up such a fashion for generations when it was plain that what I had suffered to-day they had had to suffer all the days of their lives.
It would surely be much more rational if conversation instead of dancing were made the order of the day."
The appearances, beyond all rational doubt, observed in that case are the appearances observed in Mr.
It was easy to decide that she was still too young; and Jane remained with them, sharing, as another daughter, in all the rational pleasures of an elegant society, and a judicious mixture of home and amusement, with only the drawback of the future, the sobering suggestions of her own good understanding to remind her that all this might soon be over.
She obstinately refuses, however, to accept this rational view.
In the earlier series of books containing, among others, Bosanquet's "History of Aesthetic," Pfleiderer's "Rational Theology since Kant," Albee's "History of English Utilitarianism," Bonar's "Philosophy and Political Economy," Brett's "History of Psychology," Ritchie's "Natural Rights," these objects were to a large extent effected.