Mawson, C.O.S., ed. (1870–1938). Roget’s International Thesaurus. 1922.

Class IV. Words Relating to the Intellectual Faculties
Division (I) Formation of Ideas
Section III. Materials for Reasoning

474. Certainty.

   NOUN:CERTAINTY; necessity [See Necessity]; certitude, sureness, surety, assurance; dead -, moral- certainty; infallibleness &c. adj.; infallibility, reliability, reliableness; indubitableness, inevitableness, unquestionableness.
  gospel, scripture, church, pope, court of final appeal; res adjudicata, [L.], res judicata [L.]; ultimatum.
  FACT; positive fact, matter of fact; fait accompli [F.].
  BIGOTRY, positiveness, dogmatism, dogmatization; fanaticism.
  DOGMATIST, dogmatizer, doctrinaire, bigot, opinionist, Sir Oracle; dogmatic theorist; zealot, fanatic; ipse dixit [L.].
   VERB:BE CERTAIN &c. adj.; stand to reason.
  RENDER CERTAIN &c. adj.; insure or ensure, assure; clinch, make sure; determine, find out once for all, decide, set at rest, “make assurance double sure” [Macbeth]; know (believe) [See Belief]; dismiss all doubt, admit of no doubt.
  DOGMATIZE, lay down the law.
   ADJECTIVE:CERTAIN, sure; assured &c. v.; solid, well-founded.
  UNQUALIFIED, absolute, positive, determinate, definite, clear, unequivocal, categorical, unmistakable, decisive, decided, ascertained.
  INEVITABLE, unavoidable, avoidless; ineluctable.
  CONCLUSIVE, unimpeachable, undeniable, unquestionable; indefeasible, indisputable, incontestable, incontrovertible, indubitable; irrefutable (proven) [See Demonstration]; without power of appeal, inappealable, final.
  INDUBIOUS; without -, beyond a -, without a shade or shadow of- -doubt, – question; past dispute; clear as day; beyond all -question, – dispute; undoubted, uncontested, unquestioned, undisputed; questionless, doubtless.
  AUTHORITATIVE, authentic, official, governmental, curule.
  sure as -fate, – death and taxes, – a gun [colloq.].
  EVIDENT, self-evident, axiomatic; clear, – as day, – as the sun at noonday; apparent (manifest) [See Manifestation].
  INFALLIBLE, unerring; unchangeable [See Stability]; to be depended on, trustworthy, reliable, bound.
  DOGMATIC, opinionative, opinionated, dictatorial, doctrinaire; fanatical, bigoted.
   ADVERB:CERTAINLY &c. adj.; for certain, certes [archaic], sure, no doubt, doubtless, and no mistake [colloq.], flagrante delicto [L.]; sure enough, to be sure, of course, as a matter of course, à coup sur [F.], sans doute [F.], questionless [rare], for a certainty, of a certainty, to a certainty; in truth (truly) [See Truth]; at any rate, at all events; without fail; coûte que coûte [F.], coûte qu’il coûte [F.]; whatever may happen, if the worse come to the worst; come what may, come what will, happen what may, happen what will; sink or swim; rain or shine, live or die.
  1. Cela va sans dire.
  2. There is -no question, – not a shadow of doubt.
  3. The die is cast (necessity) [See Necessity].
  4. Facts are stubborn things.—Smollett