... infallible; unchangeable &c. 150; to be depended on, trustworthy, reliable, bound. unimpeachable, undeniable, unquestionable; indisputable, incontestable, incontrovertible, indubitable; irrefutable &c. (proven) 478; conclusive, without power of appeal. indubious[obs3]; without doubt, beyond a doubt, without a shade or shadow of doubt, without question, beyond question; past dispute; clear as day; beyond all question, beyond all dispute; undoubted, uncontested, unquestioned, undisputed; questionless[obs3], ... — Roget's Thesaurus
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