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.

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

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.

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.
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"

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

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:
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

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

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

rational

[ˈræʃənl] adj (being) → razionale (Med) (lucid) → lucido/a; (faculty, action, argument) → razionale; (solution, explanation, reasoning) → logico/a, razionale

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

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

ra·tion·al

a. racional, cuerdo-a, basado-a en la razón.
References in classic literature ?
Here I was, a giant among pig- mies, a man among children, a master intelligence among intellectual moles: by all rational measurement the one and only actually great man in that whole British world; and yet there and then, just as in the remote England of my birth-time, the sheep-witted earl who could claim long descent from a king's leman, acquired at second-hand from the slums of London, was a better man than I was.
She made this sacrifice as a matter of religious etiquette; as a thing necessary just now, but by no means to be wrested into a precedent; no, a week or two would limber up her piety, then she would be rational again, and the next two dollars that got left out in the cold would find a comforter--and she could name the comforter.
He could not meet her in conversation, rational or playful.
Elinor agreed to it all, for she did not think he deserved the compliment of rational opposition.
One strong proof of my wretchedly defective nature is, that even her expostulations, so mild, so rational, have not influence to cure me of my faults; and even her praise, though I value it most highly, cannot stimulate me to continued care and foresight.
I don't know what would have concluded the scene, had there not been one person at hand rather more rational than myself, and more benevolent than my entertainer.
That would seem such a rational thing to do that no one would think it at all mysterious.
Better to be a rational creature," he added then, after ringing a small bell on the table, "and accept your natural destiny.
But it's natural and rational that you should like it.
When the robbery was talked of at the Rainbow and elsewhere, in good company, the balance continued to waver between the rational explanation founded on the tinder-box, and the theory of an impenetrable mystery that mocked investigation.
Devil with Devil damn'd Firm concord holds, men onely disagree Of Creatures rational, though under hope Of heavenly Grace: and God proclaiming peace, Yet live in hatred, enmitie, and strife Among themselves, and levie cruel warres, Wasting the Earth, each other to destroy: As if (which might induce us to accord) Man had not hellish foes anow besides, That day and night for his destruction waite.
Thou canst play the rational if thou wilt; credit me for once, and let us home ere the storm begins to rage, for the night will be fearful.