# 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 WordsSynonyms

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Noun | 1. | irrational - a real number that cannot be expressed as a rational numberreal, 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" 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*

**1.**illogical, crazy, silly, absurd, foolish, unreasonable, unwise, preposterous, idiotic, nonsensical, unsound, unthinking, injudicious, unreasoning an irrational fear of science

**sound, wise, reasonable, sensible, rational, logical, judicious, circumspect**

*illogical*## irrational

*adjective*

Not governed by or predicated on reason:

**out of bounds.**

*Idiom:*Translations

**iracionální**

**epälooginen**

**irrationaalinen**

## irrational

[ɪˈræʃ^{ə}n

*ə*l]

*adj*

[

an irrational fear of science → une peur irrationnelle de la science

*feeling, behaviour, idea, belief*] → irrationnel(le)an irrational fear of science → une peur irrationnelle de la science

## irrational

*adj*

(= illogical, also Math, Psych) → irrational;

*fear, belief*→ unsinnig, irrational; (= not sensible) → unvernünftig; he had become quite**irrational**about it → er hatte eine irrationale Einstellung dazu entwickelt; if you maintain X, then it is**irrational**to deny Y → wenn Sie X behaupten, ist es widersinnig*or*unlogisch, Y zu leugnen## irrational

[ɪˈræʃənl]*adj*→ irrazionale

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.

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