IRRATIONAL

irrational

(adjective) not consistent with or using reason; “irrational fears”; “irrational animals”

irrational

(adjective) real but not expressible as the quotient of two integers; “irrational numbers”

Source: WordNet® 3.1

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Etymology

Adjective

irrational (comparative more irrational, superlative most irrational)

Not rational; unfounded or nonsensical.

(mathematics, arithmetic, number theory, not comparable) Of a real number, that cannot be written as the ratio of two integers.

Antonym: rational

Hyponym: transcendental

Noun

irrational (plural irrationals)

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

Source: Wiktionary

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Ir*ra"tion*al, a. Etym: [L. irrationalis: cf. F. irrationnel. See In- not, and Rational.]

1. Not rational; void of reason or understanding; as, brutes are irrational animals.

2. Not according to reason; absurd; foolish. It seemed utterly irrational any longer to maintain it. I. Taylor.

3. (Math.)

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

Syn.

– Absurd; foolish; preposterous; unreasonable; senseless. See Absurd.

Source: Webster’s Unabridged Dictionary 1913 Edition

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