Irrational

Pronunciation

• enPR: Ä­ră'sh(É™)nÉ™l, IPA: /ɪˈræʃ.(É™.)nÉ™l/

Origin

From Latin irratiōnālis, from ir- + ratiōnālis.

Full definition of irrational

Adjective

1. Not rational; unfounded or nonsensical.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.
2. (mathematics, arithmetic, number theory, not comparable) Of a real number, that cannot be written as the ratio of two integers.The number π is irrational.

Antonyms

• (mathematics) rational

Hyponyms

• (mathematics) transcendental

Derived terms

• irrational number
• irrationality
• irrationalize
• irrationalization

Noun

1. A real number that can not be expressed as the quotient of two integers, an irrational number.
• 1946, Bertrand Russell, History of Western Philosophy, I.24: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.