What does Irrational mean?

Definitions for Irrationalɪˈræʃ ə nl

Here are all the possible meanings and translations of the word Irrational.

Princeton's WordNet

  1. irrational number, irrational(adj)

    a real number that cannot be expressed as a rational number

  2. irrational(adj)

    not consistent with or using reason

    "irrational fears"; "irrational animals"

  3. irrational(adj)

    real but not expressible as the quotient of two integers

    "irrational numbers"


  1. irrational(a.)

    Not according to reason; having no rational basis; clearly contrary to reason; easily disproved by reasoning; absurd; -- of assertions and beliefs. Hence, of actions: foolish; unreasonable.

  2. Origin: [L. irrationalis: cf. F. irrationnel. See In- not, and Rational.]


  1. irrational(Noun)

    A real number that can not be expressed as the quotient of two integers, an irrational number.

  2. irrational(Adjective)

    Not rational; unfounded or nonsensical.

    an irrational decision

  3. irrational(Adjective)

    Of a real number, that cannot be written as the ratio of two integers.

    The number uE0009599uE001 is irrational.

  4. Origin: From irrationalis, from ir- + rationalis.

Webster Dictionary

  1. Irrational(adj)

    not rational; void of reason or understanding; as, brutes are irrational animals

  2. Irrational(adj)

    not according to reason; absurd; foolish

  3. Irrational(adj)

    not capable of being exactly expressed by an integral number, or by a vulgar fraction; surd; -- said especially of roots. See Surd

  4. Origin: [L. irrationalis: cf. F. irrationnel. See In- not, and Rational.]

Chambers 20th Century Dictionary

  1. Irrational

    ir-rash′un-al, adj. void of reason or understanding: absurd.—n. Irrational′ity.—adv. Irra′tionally.—Irrational numbers, a term applied to those roots of numbers which cannot be accurately expressed by a finite number of figures—e.g. √2 is an irrational number.


  1. Chaldean Numerology

    The numerical value of Irrational in Chaldean Numerology is: 9

  2. Pythagorean Numerology

    The numerical value of Irrational in Pythagorean Numerology is: 9

Sample Sentences & Example Usage

  1. Lisa Hoffman:

    Love is like pi - natural, irrational, and very important.

  2. Scott Adams:

    We expect others to act rationally even though we are irrational.

  3. Slovakian Prime Minister Robert Fico:

    The quota system is irrational, and in our opinion will end up in disgrace.

  4. Alan Greenspan:

    How do we know when irrational exuberance has unduly escalated asset values

  5. Doctor Who:

    It may be irrational of me, but human beings are quite my favorite species.

Images & Illustrations of Irrational

  1. IrrationalIrrationalIrrational

Translations for Irrational

From our Multilingual Translation Dictionary

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"Irrational." Definitions.net. STANDS4 LLC, 2018. Web. 23 Feb. 2018. <https://www.definitions.net/definition/Irrational>.

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