THESAURUS
Impossible
I refuse, I will not, absurd, algorismic, algorithmic, aliquot, antic, barred, by no means, cardinal, closed-out, contrary to reason, count me out, crazy, cureless, decimal, differential, digital, even, exceptionable, excluded, exponential, fanciful, fantastic, farcical, figural, figurate, figurative, finite, fractional, hopeless, illogical, imaginary, immedicable, impair, impracticable, impractical, inadmissible, include me out, incomprehensible, inconceivable, incredible, incurable, indefensible, infeasible, infinite, integral, intolerable, irrational, irremediable, irreparable, logarithmic, logically impossible, logometric, ludicrous, negative, no, no go, not likely, not possible, nothing doing, numeral, numerary, numerative, numeric, objectionable, odd, ordinal, outlandish, outrageous, oxymoronic, pair, paradoxical, positive, possible, preposterous, prime, prohibited, radical, rational, real, reciprocal, ridiculous, ruled-out, self-contradictory, submultiple, surd, transcendental, unacceptable, unaccountable, unachievable, unattainable, unbelievable, uncorrectable, undesirable, unexpected, unfeasible, unimaginable, unobtainable, unrealizable, unreasonable, unsolvable, unsuitable, untenable, unthinkable, unworkable, weird
ROGET THESAURUS
Impossible
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.
Refusal
N
refusal, rejection, noncompliance, incompliance, denial, declining, declension, declinature, peremptory refusal, flat refusal, point blank refusal, repulse, rebuff, discountenance, recusancy, abnegation, protest, disclaimer, dissent, revocation, refusing, restive, restiff, recusant, uncomplying, unconsenting, not willing to hear of, deaf to, refused, ungranted, out of the question, not to be thought of, impossible, no, on no account, not for the world, no thank you, thanks but no thanks, non possumus, your humble servant, bien oblige, not on your life, no way, not even if you beg on your knees.
Impossibility
N
impossibility, what cannot, what can never be, sour grapes, hopelessness, impossible, not possible, absurd, contrary to reason, unlikely, unreasonable, incredible, beyond the bounds of reason, beyond the bounds of possibility, beyond the realm of possibility, from which reason recoils, visionary, inconceivable, prodigious, unimaginable, inimaginable, unthinkable, impracticable unachievable, unfeasible, infeasible, insuperable, unsurmountable, insurmountable, unattainable, unobtainable, out of reach, out of the question, not to be had, not to be thought of, beyond control, desperate, incompatible, inaccessible, uncomeatable, impassable, impervious, innavigable, inextricable, self- contradictory, out of one's power, beyond one's power, beyond one's depth, beyond one's reach, beyond one's grasp, too much for, ultra crepidam, the grapes are sour, non possumus, non nostrum tantas componere lites, look for a needle in a haystack, chercher une aiguille dans une botte de foin, il a le mer +a boire.
Doubt
N
unbelief doubt, unbelief, disbelief, misbelief, discredit, miscreance, infidelity, dissent, change of opinion, retraction, doubt, skepticism, scepticism, misgiving, demure, distrust, mistrust, cynicism, misdoubt, suspicion, jealousy, scruple, qualm, onus probandi, incredibility, incredibleness, incredulity, doubter, skeptic, cynic, unbeliever, unbelieving, skeptical, sceptical, incredulous as to, skeptical as to, distrustful as to, shy as to, suspicious of, doubting, doubtful, disputable, unworthy of, undeserving of belief, questionable, suspect, suspicious, open to suspicion, open to doubt, staggering, hard to believe, incredible, unbelievable, not to be believed, inconceivable, impossible, fallible, undemonstrable, controvertible, cum grano salis, with a grain of salt, with grains of allowance, fronti nulla fides, nimium ne crede colori, timeo Danaos et dona ferentes, I fear the Greeks even when bearing gifts, beware of Greeks bearing gifts, credat Judaeus Apella, let those believe who may, ad tristem partem stenua est suspicio.