impossible

Synonyms: absurd beyond contrary to reason cureless futile hardly possible hopeless hundred-to-one impassable impervious impracticable impractical inaccessible inconceivable inexecutable infeasible insurmountable irrealizable irreparable no-go not a prayer no-way no-win out of the question preposterous too much unachievable unattainable uncorrectable unfeasible unimaginable unobtainable unreasonable unrecoverable unthinkable unworkable useless visionary way out

Antonyms: achievable believable obtainable possible reasonable tenable

Synonyms: absurd egregious hopeless improper incongruous ludicrous objectionable offensive outrageous preposterous unacceptable unanswerable undesirable unreasonable unsuitable

Antonyms: behaving good governable manageable tolerable