Word Study
irrational
CIDE DICTIONARY
- Not rational; void of reason or understanding; as, brutes are irrational animals. [1913 Webster]
- Not according to reason; having no rational basis; clearly contrary to reason; easily disproved by reasoning; absurd; -- of assertions and beliefs. [1913 Webster]"It seemed utterly irrational any longer to maintain it." [1913 Webster]
- 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.
OXFORD DICTIONARY
irrational, adj.
1 illogical; unreasonable.
2 not endowed with reason.
3 Math. (of a root etc.) not rational; not commensurate with the natural numbers (e.g. a non-terminating decimal).
1 illogical; unreasonable.
2 not endowed with reason.
3 Math. (of a root etc.) not rational; not commensurate with the natural numbers (e.g. a non-terminating decimal).
Derivative
irrationality n. irrationalize v.tr. (also -ise). irrationally adv.
Etymology
L irrationalis (as IN-(1), RATIONAL)
THESAURUS
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, zealoticROGET THESAURUS
irrational
Number
N number, symbol, numeral, figure, cipher, digit, integer, counter, round number, formula, function, series, sum, difference, complement, subtrahend, product, multiplicand, multiplier, multiplicator, coefficient, multiple, dividend, divisor, factor, quotient, submultiple, fraction, rational number, surd, irrational number, transcendental number, mixed number, complex number, complex conjugate, numerator, denominator, decimal, circulating decimal, repetend, common measure, aliquot part, prime number, prime, relative prime, prime factor, prime pair, reciprocal, totient, binary number, octal number, hexadecimal number, permutation, combination, variation, election, ratio, proportion, comparison, progression, arithmetical progression, geometrical progression, harmonical progression, percentage, permilage, figurate numbers, pyramidal numbers, polygonal numbers, power, root, exponent, index, logarithm, antilogarithm, modulus, base, differential, integral, fluxion, fluent, numeral, complementary, divisible, aliquot, reciprocal, prime, relatively prime, fractional, decimal, figurate, incommensurable, proportional, exponential, logarithmic, logometric, differential, fluxional, integral, totitive, positive, negative, rational, irrational, surd, radical, real, complex, imaginary, finite, infinite, impossible, numerically, modulo.& Sophistry
N intuition, instinct, association, hunch, gut feeling, presentiment, premonition, rule of thumb, superstition, astrology, faith (supposition), sophistry, paralogy, perversion, casuistry, jesuitry, equivocation, evasion, chicane, chicanery, quiddet, quiddity, mystification, special pleading, speciousness, nonsense, word sense, tongue sense, false reasoning, vicious reasoning, circular reasoning, petitio principii, ignoratio elenchi, post hoc ergo propter hoc, non sequitur, ignotum per ignotius, misjudgment, false teaching, sophism, solecism, paralogism, quibble, quirk, elenchus, elench, fallacy, quodlibet, subterfuge, subtlety, quillet, inconsistency, antilogy, a delusion, a mockery, and a snare, claptrap, cant, mere words, lame and impotent conclusion, meshes of sophistry, cobwebs of sophistry, flaw in an argument, weak point, bad case, overrefinement, hairsplitting, intuitive, instinctive, impulsive, independent of reason, anterior to reason, gratuitous, hazarded, unconnected, unreasonable, illogical, false, unsound, invalid, unwarranted, not following, inconsequent, inconsequential, inconsistent, absonous, absonant, unscientific, untenable, inconclusive, incorrect, fallacious, fallible, groundless, unproved, non sequitur, it does not follow, deceptive, sophistical, jesuitical, illusive, illusory, specious, hollow, plausible, ad captandum, evasive, irrelevant, weak, feeble, poor, flimsy, loose, vague, irrational, nonsensical, foolish, frivolous, pettifogging, quibbling, finespun, overrefined, at the end of one's tether, au bout de son latin, intuitively, by intuition, illogically, non constat, that goes for nothing.Folly
N imbecility folly, want of intelligence &c, want of intellect, shadowness, silliness, foolishness, imbecility, incapacity, vacancy of mind, poverty of intellect, weakness of intellect, clouded perception, poor head, apartments to let, stupidity, stolidity, hebetude, dull understanding, meanest capacity, shortsightedness, incompetence, one's weak side, not one's strong point, bias, infatuation, simplicity, puerility, babyhood, dotage, anility, second childishness, fatuity, idiocy, idiotism, driveling, folly, frivolity, irrationality, trifling, ineptitude, nugacity, inconsistency, lip wisdom, conceit, sophistry, giddiness, eccentricity, extravagance, rashness, act of folly, unintelligent, unintellectual, unreasoning, mindless, witless, reasoningless, brainless, halfbaked, having no head, not bright, inapprehensible, weak headed, addle headed, puzzle headed, blunder headed, muddle headed, muddy headed, pig headed, beetle headed, buffle headed, chuckle headed, mutton headed, maggoty headed, grossheaded, beef headed, fat witted, fat-headed, weak-minded, feeble-minded, dull minded, shallow minded, lack- brained, rattle-brained, rattle headed, half witted, lean witted, short witted, dull witted, blunt-witted, shallow-pated, clod-pated, addle- pated, addle-brained, dim-sighted, short-sighted, thick-skulled, weak in the upper story, shallow, borne, weak, wanting, soft, sappy, spoony, dull, dull as a beetle, stupid, heavy, insulse, obtuse, blunt, stolid, doltish, asinine, inapt, prosaic, hebetudinous, childish, child-like, infantine, infantile, babyish, babish, puerile, anile, simple, old-womanish, fatuous, idiotic, imbecile, driveling, blatant, babbling, vacant, sottish, bewildered, blockish, unteachable Boeotian, Boeotic, bovine, ungifted, undiscerning, unenlightened, unwise, unphilosophical, apish, simious, foolish, silly, senseless, irrational, insensate, nonsensical, inept, maudlin, narrow-minded, bigoted, giddy, rash, eccentric, foolish, unwise, injudicious, improper, unreasonable, without reason, ridiculous, absurd, idiotic, silly, stupid, asinine, ill-imagined, ill-advised, ill-judged, ill-devised, mal entendu, inconsistent, irrational, unphilosophical, extravagant, sleeveless, idle, pointless, useless, inexpedient, frivolous, Davus sum non, a fool's bolt is soon shot clitellae bovi sunt im, fools rush in where angels fear to tread, il n' a ni bouche ni eperon, the bookful blockhead, ignorantly read, to varnish nonsense with the charms of sound, imbecility folly, want of intelligence &c, want of intellect, shadowness, silliness, foolishness, imbecility, incapacity, vacancy of mind, poverty of intellect, weakness of intellect, clouded perception, poor head, apartments to let, stupidity, stolidity, hebetude, dull understanding, meanest capacity, shortsightedness, incompetence, one's weak side, not one's strong point, bias, infatuation, simplicity, puerility, babyhood, dotage, anility, second childishness, fatuity, idiocy, idiotism, driveling, folly, frivolity, irrationality, trifling, ineptitude, nugacity, inconsistency, lip wisdom, conceit, sophistry, giddiness, eccentricity, extravagance, rashness, act of folly, unintelligent, unintellectual, unreasoning, mindless, witless, reasoningless, brainless, halfbaked, having no head, not bright, inapprehensible, weak headed, addle headed, puzzle headed, blunder headed, muddle headed, muddy headed, pig headed, beetle headed, buffle headed, chuckle headed, mutton headed, maggoty headed, grossheaded, beef headed, fat witted, fat-headed, weak-minded, feeble-minded, dull minded, shallow minded, lack- brained, rattle-brained, rattle headed, half witted, lean witted, short witted, dull witted, blunt-witted, shallow-pated, clod-pated, addle- pated, addle-brained, dim-sighted, short-sighted, thick-skulled, weak in the upper story, shallow, borne, weak, wanting, soft, sappy, spoony, dull, dull as a beetle, stupid, heavy, insulse, obtuse, blunt, stolid, doltish, asinine, inapt, prosaic, hebetudinous, childish, child-like, infantine, infantile, babyish, babish, puerile, anile, simple, old-womanish, fatuous, idiotic, imbecile, driveling, blatant, babbling, vacant, sottish, bewildered, blockish, unteachable Boeotian, Boeotic, bovine, ungifted, undiscerning, unenlightened, unwise, unphilosophical, apish, simious, foolish, silly, senseless, irrational, insensate, nonsensical, inept, maudlin, narrow-minded, bigoted, giddy, rash, eccentric, foolish, unwise, injudicious, improper, unreasonable, without reason, ridiculous, absurd, idiotic, silly, stupid, asinine, ill-imagined, ill-advised, ill-judged, ill-devised, mal entendu, inconsistent, irrational, unphilosophical, extravagant, sleeveless, idle, pointless, useless, inexpedient, frivolous, Davus sum non, a fool's bolt is soon shot clitellae bovi sunt im, fools rush in where angels fear to tread, il n' a ni bouche ni eperon, the bookful blockhead, ignorantly read, to varnish nonsense with the charms of sound.For 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