proof

noun
\ ˈprüf How to pronounce proof (audio) \

Definition of proof

 (Entry 1 of 3)

1a : 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
6a 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
8a : 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

proof

adjective

Definition of proof (Entry 2 of 3)

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

proof

verb
proofed; proofing; proofs

Definition of proof (Entry 3 of 3)

transitive verb

1a : 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

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Other Words from proof

Verb

proofer noun

Examples of proof in a Sentence

Noun

The document was proof that her story was true. He claims that he was home when the murder was committed, but he has no proof. The proof shows that the theorem is true.

Verb

She proofed the story carefully.
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Recent Examples on the Web: Noun

Then, last week, Equifax sent a spammy-looking email demanding further proof from people who had claimed the money. Adam Lashinsky, Fortune, "Why Cities Need to De-Emphasize Cars and Turn Streets Into Parks—Data Sheet," 17 Sep. 2019 Bear in mind, moreover, that a grand jury, unlike a trial jury, is not being asked to find proof beyond a reasonable doubt. Andrew C. Mccarthy, National Review, "Why It’s Unlikely the McCabe Grand Jury Voted against Indictment," 14 Sep. 2019 Line a broiler-proof rimmed baking sheet with nonstick foil. Danielle Pointdujour, Essence, "Three Delicious Recipes To Fill You Up And Protect Your Heart," 10 Sep. 2019 Dumpsters should always be closed securely with a bear-proof bar so a bear can’t open the lid and climb inside, Clay said. Kirk Mitchell, The Denver Post, "Bear cub crushed when dumpster toppled onto its neck in Jefferson County," 9 Sep. 2019 Since Dorian devastated the islands earlier this month, killing at least 44 people, hundreds of Bahamian refugees have reportedly come to the United States after going through a screening process with only a passport and proof of no criminal record. oregonlive, "Bahamas hurricane survivors kicked off ferry over U.S. visa demands," 9 Sep. 2019 Since India cannot offer documentary proof to establish the nationality of these individuals, Bangladesh has no reason to accept anyone who is deported after the NRC exercise. Smitana Saikia, Quartz India, "Why is the Modi government so shrill about finding and deporting illegal immigrants?," 5 Sep. 2019 Make sure coop is rat proof by closing up any holes bigger than a nickel. oregonlive.com, "Follow these tips to keep rats out of homes and gardens," 27 Aug. 2019 They are grounded in mathematical rigor and experimental proof. George Musser, Scientific American, "The Search for Truth in Physics," 25 Aug. 2019

Recent Examples on the Web: Adjective

Gardner’s support would have been one step closer to a veto-proof majority. The Denver Post Editorial Board, The Denver Post, "Editorial: Now we know Gardner failed to protect Colorado from cuts in addition to failing the U.S. Constitution," 8 Sep. 2019 Even the bolts must have tamper-proof heads that cannot be loosened with ordinary wrenches, to prevent the kind of vandal who would try to take apart a kiddie playground. Steve Rubenstein, SFChronicle.com, "Work is child’s play as Napa volunteer, 92, keeps building swings and slides," 30 Aug. 2019 In response, the government revoked the law requiring tamper-proof tape. The Economist, "How Viktor Orban hollowed out Hungary’s democracy," 29 Aug. 2019 And in Utah, where Republicans hold a veto-proof majority in both chambers, the state's Republican governor signed a law allowing educators to discuss contraception in public school classrooms. NBC News, "How #MeToo is changing sex ed policies, even in red states," 8 Aug. 2019 All of this will be driven by blockchain technology, which creates a permanent tamper-proof ledger of property and transactions. Jeff John Roberts, Fortune, "Want to Own Kawhi’s Jump Shot? NBA and Crypto Kitties Maker Launch Digital Collectibles," 31 July 2019 Shortly after the Zomato personnel’s video went viral on social media, the firm launched tamper-proof packaging in 10 cities. Ananya Bhattacharya, Quartz India, "India’s food delivery wars are no longer about speed, but quality," 24 July 2019 But the idea of creating tamper-proof databases has captured the attention of everyone from anarchist techies to staid bankers. Klint Finley, WIRED, "The WIRED Guide to the Blockchain," 9 July 2019 Its modest task is to determine whether a significantly lower proof hurdle — probable cause — has been met. Andrew C. Mccarthy, National Review, "Why It’s Unlikely the McCabe Grand Jury Voted against Indictment," 14 Sep. 2019

Recent Examples on the Web: Verb

To note, this dough will proof/rise considerably, so make sure your container is at least 3 times as large as the dough. Kristen Farmer Hall, al, "Learn to make brioche and shortbread from a local baker," 27 Aug. 2019 Our favorite self-closing outlet covers to keep kids safe For new parents, baby-proofing your home can be a challenge. Valerie Li, USA TODAY, "These are the best Prime Day deals under $10," 15 July 2019 Calipari has often cited Kentucky's rigorous compliance department as proof the program is not involved in the scandal that has rocked the sport. Jon Hale, The Courier-Journal, "John Calipari not worried about Kenny Payne text messages in Michael Avenatti case," 9 July 2019 Inconsistencies in the victim’s account, as well as unreliable forensic computer investigations, Gibbs said, will not add up to proof beyond a reasonable doubt. Clifford Ward, chicagotribune.com, "Trial begins in DuPage County for former nurse from South Elgin accused of transmitting sexual images from patient’s phone to his own," 27 Aug. 2019 Set in a warm place to proof until doubled in size, about 2 hours. Los Angeles Times, "How to make the best kolaches from our favorite NYC pastry chef," 26 Aug. 2019 After rat-proofing the building, residents should live-trap and remove any rats still inside. Colin Campbell, baltimoresun.com, "PETA billboard in Baltimore calls Jared Kushner ‘rich pest,' urges humane rat control," 19 Aug. 2019 Among the bill’s provisions, utilities will spend $5 billion on fire-proofing measures for their equipment — things like insulating transmission and distribution lines and replacing more wooden poles with fire-resistant steel poles. Rob Nikolewski, San Diego Union-Tribune, "Lawsuit filed to stop California’s new wildfire liability law," 19 July 2019 That money is expected to fund $500 million worth of flood-proofing infrastructure. Alex Harris, sun-sentinel.com, "Adapting to climate change is going to cost Florida a lot. Who’s going to pay for it?," 13 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'proof.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of proof

Noun

13th century, in the meaning defined at sense 1a

Adjective

1583, in the meaning defined at sense 1

Verb

circa 1699, in the meaning defined at sense 1a

History and Etymology for proof

Noun

Middle English prof, prove, alteration of preve, from Anglo-French preove, from Late Latin proba, from Latin probare to prove — more at prove

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Statistics for proof

Last Updated

1 Oct 2019

Look-up Popularity

Time Traveler for proof

The first known use of proof was in the 13th century

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More Definitions for proof

proof

noun

English Language Learners Definition of proof

 (Entry 1 of 2)

: something which shows that something else is true or correct
: an act or process of showing that something is true
mathematics : a test which shows that a calculation is correct

proof

adjective

English Language Learners Definition of proof (Entry 2 of 2)

formal : designed or made to prevent or protect against something harmful

proof

noun
\ ˈprüf How to pronounce proof (audio) \

Kids Definition of proof

 (Entry 1 of 2)

1 : evidence of truth or correctness “… Is there any clear proof … or is it mere hearsay?”— Robert Lawson, Rabbit Hill
2 : a printing (as from type) prepared for study and correction
3 : a test print made from a photographic negative
4 : test entry 1 sense 2 Let's put her theory to the proof.

proof

adjective

Kids Definition of proof (Entry 2 of 2)

: able to keep out something that could be harmful The seal on the bottle is proof against tampering.
Hint: The adjective proof is usually used in compounds. waterproof

proof

noun

Legal Definition of proof

1 : the effect of evidence sufficient to persuade a reasonable person that a particular fact exists — see also evidence
2 : the establishment or persuasion by evidence that a particular fact exists — see also burden of proof
3 : something (as evidence) that proves or tends to prove the existence of a particular fact — see also clear and convincing, preponderance of the evidence, reasonable doubt, standard of proof — compare allegation, argument

History and Etymology for proof

alteration of Middle English preove, from Old French preuve, from Late Latin proba, from Latin probare to prove

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More from Merriam-Webster on proof

Rhyming Dictionary: Words that rhyme with proof

Thesaurus: All synonyms and antonyms for proof

Spanish Central: Translation of proof

Nglish: Translation of proof for Spanish Speakers

Britannica English: Translation of proof for Arabic Speakers

Britannica.com: Encyclopedia article about proof

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