Irrational

/ɪˈɹæʃ.(ə.)nəl/ · adjective

Meaning

Not rational; unfounded, nonsensical or wrong-headed..

Definitions by Sense

1. Not rational; unfounded, nonsensical or wrong-headed.
2. (mathematics, arithmetic, number theory, not comparable) Of a real number, that cannot be written as the ratio of two integers.
3. (mathematics) A real number that can not be expressed as the quotient of two integers, an irrational number.

Example Sentences

an irrational decision

July 18, 2012, Scott Tobias, AV Club The Dark Knight Riseshttp://www.avclub.com/articles/the-dark-knight-rises-review-batman,82624/ Where the Joker preys on our fears of random, irrational acts of terror, Bane has an all-consuming, dictatorial agenda that’s more stable and permanent, a New World Order that’s been planned out with the precision of a military coup.

The number π is irrational.

The square root of 2, which was the first irrational to be discovered, was known to the early Pythagoreans, and ingenious methods of approximating to its value were discovered.

Synonyms for irrational

Antonyms for irrational

Related Words

Word Forms

• more irrational
• most irrational
• irrationals

Usage Notes

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