Proof  —n. 1 facts, evidence, reasoning, etc. Establishing or helping to establish a fact (no proof that he was there). 2 demonstration, proving (not capable of proof). 3 test, trial (put them to the proof). 4 standard of strength of distilled alcohol. 5 trial impression from type or film, for correcting before final printing. 6 step by step resolution of a mathematical or philosophical problem. 7 photographic print made for selection etc. —adj. 1 (often in comb.) Impervious to penetration, ill effects, etc., esp. By a specified agent (proof against corruption; childproof). 2 being of proof alcoholic strength. —v. 1 make proof, esp. Make (fabric) waterproof. 2 make a proof of (a printed work). [latin proba: related to *prove]