irrational


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ir·ra·tion·al

 (ĭ-răsh′ə-nəl)
adj.
1.
a. Not endowed with reason.
b. Affected by loss of usual or normal mental clarity; incoherent, as from shock.
c. Marked by a lack of accord with reason or sound judgment: an irrational dislike.
2.
a. Being a syllable in Greek and Latin prosody whose length does not fit the metric pattern.
b. Being a metric foot containing such a syllable.
3. Mathematics Of or relating to an irrational number.
n. Mathematics
An irrational number.

ir·ra′tion·al·ly adv.
ir·ra′tion·al·ness n.

irrational

(ɪˈræʃənəl)
adj
1. inconsistent with reason or logic; illogical; absurd
2. incapable of reasoning
3. (Mathematics) maths
a. not rational
b. (as noun): an irrational.
4. (Poetry) prosody (in Greek or Latin verse)
a. of or relating to a metrical irregularity, usually the occurrence of a long syllable instead of a short one
b. denoting a metrical foot where such an irregularity occurs
irˈrationally adv
irˈrationalness n

ir•ra•tion•al

(ɪˈræʃ ə nl)

adj.
1. lacking the faculty of reason; deprived of reason.
2. lacking sound judgment or logic: irrational arguments.
3. not controlled or governed by reason: irrational behavior.
4.
a. (of a number) not capable of being expressed exactly as a ratio of two integers.
b. (of a function) not capable of being expressed exactly as a ratio of two polynomials.
c. (of an equation) having an unknown under a radical sign or, alternately, with a fractional exponent.
5. of or pertaining to a syllable in Greek or Latin prosody whose quantity does not fit the meter.
n.
[1425–75; late Middle English < Latin]
ir•ra′tion•al•ly, adv.
ir•ra′tion•al•ness, n.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.irrational - a real number that cannot be expressed as a rational number
real, real number - any rational or irrational number
transcendental number - an irrational number that is not algebraic
algebraic number - root of an algebraic equation with rational coefficients
Adj.1.irrational - not consistent with or using reason; "irrational fears"; "irrational animals"
incoherent - without logical or meaningful connection; "a turgid incoherent presentation"
illogical, unlogical - lacking in correct logical relation
unreasonable - not reasonable; not showing good judgment
rational - consistent with or based on or using reason; "rational behavior"; "a process of rational inference"; "rational thought"
2.irrational - real but not expressible as the quotient of two integers; "irrational numbers"
math, mathematics, maths - a science (or group of related sciences) dealing with the logic of quantity and shape and arrangement
rational - capable of being expressed as a quotient of integers; "rational numbers"

irrational

adjective
2. senseless, wild, crazy, unstable, insane, mindless, demented, aberrant, brainless They behaved in such a bizarre and irrational manner.

irrational

adjective
Not governed by or predicated on reason:
Translations
iracionální
epälooginenirrationaalinen

irrational

[ɪˈræʃənl] ADJ [behaviour, person, belief] → irracional

irrational

[ɪˈræʃənəl] adj
[feeling, behaviour, idea, belief] → irrationnel(le)
an irrational fear of science → une peur irrationnelle de la science
[argument] → irrationnel(le)
to be irrational → être irrationnel

irrational

adj
(= illogical, also Math, Psych) → irrational; fear, beliefunsinnig, irrational; (= not sensible)unvernünftig; he had become quite irrational about iter hatte eine irrationale Einstellung dazu entwickelt; if you maintain X, then it is irrational to deny Ywenn Sie X behaupten, ist es widersinnig or unlogisch, Y zu leugnen
(= not having reason) animalvernunftlos

irrational

[ɪˈræʃənl] adjirrazionale
an irrational fear → una paura irrazionale
he had become quite irrational about it → era diventato piuttosto irragionevole al riguardo

ir·ra·tion·al

n. irracional.
References in classic literature ?
If the irrational cannot be excluded, it should be outside the scope of the tragedy.
In being compelled to labor, not for himself, but for a master; in being vendible by one master to another master; and in being subject at all times to be restrained in his liberty and chastised in his body, by the capricious will of another -- the slave may appear to be degraded from the human rank, and classed with those irrational animals which fall under the legal denomination of property.
Alexey Alexandrovitch was standing face to face with life, with the possibility of his wife's loving someone other than himself, and this seemed to him very irrational and incomprehensible because it was life itself.
The palace of crystal may be an idle dream, it may be that it is inconsistent with the laws of nature and that I have invented it only through my own stupidity, through the old-fashioned irrational habits of my generation.
And Prince Andrew, crossing his arms behind him, long paced the room, now frowning, now smiling, as he reflected on those irrational, inexpressible thoughts, secret as a crime, which altered his whole life and were connected with Pierre, with fame, with the girl at the window, the oak, and woman's beauty and love.
Neither in the inconceivable could ye have been born, nor in the irrational.
And brave as he might be, it was that sort of bravery chiefly, visible in some intrepid men, which, while generally abiding firm in the conflict with seas, or winds, or whales, or any of the ordinary irrational horrors of the world, yet cannot withstand those more terrific, because more spiritual terrors, which sometimes menace you from the concentrating brow of an enraged and mighty man.
for he who is intemperate [1260a] and a coward will never do what he ought: it is evident then that both parties ought to be virtuous; but there is a difference between them, as there is between those who by nature command and who by nature obey, and this originates in the soul; for in this nature has planted the governing and submitting principle, the virtues of which we say are different, as are those of a rational and an irrational being.
These unhappy people were proposing schemes for persuading monarchs to choose favourites upon the score of their wisdom, capacity, and virtue; of teaching ministers to consult the public good; of rewarding merit, great abilities, eminent services; of instructing princes to know their true interest, by placing it on the same foundation with that of their people; of choosing for employments persons qualified to exercise them, with many other wild, impossible chimeras, that never entered before into the heart of man to conceive; and confirmed in me the old observation, "that there is nothing so extravagant and irrational, which some philosophers have not maintained for truth.
Regard to the public peace, if not to the rights of the Union, would engage the citizens to whom the contagion had not communicated itself to oppose the insurgents; and if the general government should be found in practice conducive to the prosperity and felicity of the people, it were irrational to believe that they would be disinclined to its support.
With Women, we speak of "love", "duty", "right", "wrong", "pity", "hope", and other irrational and emotional conceptions, which have no existence, and the fiction of which has no object except to control feminine exuberances; but among ourselves, and in our books, we have an entirely different vocabulary and I may almost say, idiom.
She had loved, she did love still, and she had all the suffering which a warm temper and a high spirit were likely to endure under the disappointment of a dear, though irrational hope, with a strong sense of ill-usage.