proof

I. noun Etymology: Middle English prof, prove, alteration of preve, from Anglo-French preove, from Late Latin proba, from Latin probare to prove — more at prove Date: 13th century 1. a. the cogency of evidence that compels acceptance by the mind of a truth or a fact b. the process or an instance of establishing the validity of a statement especially by derivation from other statements in accordance with principles of reasoning 2. obsolete experience 3. something that induces certainty or establishes validity 4. archaic the quality or state of having been tested or tried; especially unyielding hardness 5. evidence operating to determine the finding or judgment of a tribunal 6. a. plural proofs or proof a copy (as of typeset text) made for examination or correction b. a test impression of an engraving, etching, or lithograph c. a coin that is struck from a highly polished die on a polished planchet, is not intended for circulation, and sometimes differs in metallic content from coins of identical design struck for circulation d. a test photographic print made from a negative 7. a test applied to articles or substances to determine whether they are of standard or satisfactory quality 8. a. the minimum alcoholic strength of proof spirit b. strength with reference to the standard for proof spirit; specifically alcoholic strength indicated by a number that is twice the percent by volume of alcohol present <

whiskey of 90 proof is 45 percent alcohol

> II. adjective Date: 1592 1. able to resist or repel <

boots that were…proof against cold and wet — Robertson Davies

> — often used in combination <

windproof

> 2. used in proving or testing or as a standard of comparison 3. of standard strength or quality or alcoholic content III. transitive verb Date: 1745 1. a. to make or take a proof or test of b. proofread 2. to give a resistant quality to 3. to activate (yeast) by mixing with water and sometimes sugar or milk • proofer noun