Irrational

3 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  irrational \ir*ra"tion*al\ ([i^]r*r[a^]sh"[u^]n*al), a. [L.
     irrationalis: cf. F. irrationnel. See {In-} not, and
     {Rational}.]
     [1913 Webster]
     1. Not rational; void of reason or understanding; as, brutes
        are irrational animals.


        [1913 Webster]
  
     2. Not according to reason; having no rational basis; clearly
        contrary to reason; easily disproved by reasoning; absurd;
        -- of assertions and beliefs. Hence, of actions: foolish;
        unreasonable.
        [1913 Webster +PJC]
  
              It seemed utterly irrational any longer to maintain
              it.                                   --I. Taylor.
        [1913 Webster]
  
     3. (Math.) Not capable of being exactly expressed by an
        integral number, nor by a ratio of integral numbers; surd;
        -- said especially of roots. See {Surd}.
  
     Syn: Absurd; foolish; preposterous; unreasonable; senseless.
          See {Absurd}.
          [1913 Webster]

From WordNet (r) 2.0 [wn]:

  irrational
       adj 1: not consistent with or using reason; "irrational fears";
              "irrational animals" [ant: {rational}]
       2: real but not expressible as the quotient of two integers;
          "irrational numbers" [ant: {rational}]

From Moby Thesaurus II by Grady Ward, 1.0 [moby-thes]:

  185 Moby Thesaurus words for "irrational":
     abnormal, absonant, algorismic, algorithmic, aliquot,
     bereft of reason, bigoted, brainless, brainsick, cardinal,
     contradictory, contrary to reason, crackbrained, cracked, crazed,
     crazy, daft, decimal, deluded, demented, deprived of reason,
     deranged, differential, digital, disoriented, distraught, even,
     exponential, extravagant, extreme, extremist, fallacious, fanatic,
     faulty, figural, figurate, figurative, finite, flawed, flighty,
     foolish, fractional, haggard, hallucinated, headless, ignorant,
     ill-advised, ill-considered, ill-contrived, ill-devised,
     ill-gauged, ill-judged, illogical, imaginary, impair, impolitic,
     impossible, imprudent, inadvisable, inauthentic, inconclusive,
     incongruous, inconsequent, inconsequential, inconsiderate,
     inconsistent, indiscreet, inept, inexpedient, infinite,
     injudicious, inordinate, insane, insensate, integral, invalid,
     lackbrained, lean-minded, lean-witted, loco, logarithmic,
     logometric, loose, lunatic, mad, maddened, manic, mazed, mental,
     mentally deficient, meshuggah, mindless, misadvised, misguided,
     moon-struck, myopic, negative, non compos, non compos mentis,
     nonrational, nonscientific, not all there, not bright,
     not following, not right, numeral, numerary, numerative, numeric,
     odd, of little brain, of unsound mind, off, ordinal,
     overenthusiastic, overreligious, overzealous, pair, paralogical,
     pea-brained, perfervid, pin-brained, positive, possible, prime,
     psycho, queer, rabid, radical, rational, real, reasonless,
     reciprocal, reckless, self-annulling, self-contradictory,
     self-refuting, senseless, shortsighted, sick, slackminded,
     slackwitted, sophistic, stark-mad, stark-staring mad, strange,
     submultiple, surd, tetched, thoughtless, touched, transcendental,
     ultrazealous, unadvised, unauthentic, unbalanced, unconnected,
     unconsidered, undiscerning, unforeseeing, ungifted, unhinged,
     unintellectual, unintelligent, unphilosophical, unreasonable,
     unreasoning, unreflecting, unreflective, unsane, unscientific,
     unseeing, unsensible, unsettled, unsound, untalented, unthinking,
     unthoughtful, unwise, wandering, wild-eyed, wild-looking,
     without reason, witless, zealotic