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Pronunciation:  i'rashunl

WordNet Dictionary
  1. [adj]  not consistent with or using reason; "irrational fears"; "irrational animals"
  2. [adj]  (math) real but not expressible as the quotient of two integers; "irrational numbers"

IRRATIONAL is a 10 letter word that starts with I.


 Synonyms: blind, incoherent, jaundiced, nonrational, reasonless, superstitious, unreasoning, yellow
 Antonyms: rational, rational
 See Also: illogical, unlogical, unreasonable



Webster's 1913 Dictionary
\Ir*ra"tion*al\, a. [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.) 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}.

Thesaurus Terms
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