Dictionary and Thesaurus

Definition of Irrational

• (a.) Not rational; void of reason or understanding; as, brutes are irrational animals.
• (a.) Not according to reason; absurd; foolish.
• (a.) Not capable of being exactly expressed by an integral number, or by a vulgar fraction; surd; -- said especially of roots. See Surd.

Synonyms of Irrational

• Irrational Number

Antonyms of Irrational

• Rational
• Rational

Homophones of Irrational