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

He was found to be under the influence of opiates and in possession of Xanax without proof of prescription. Jake Richardson, The Mercury News, "Campbell crime report for the week of Sept. 6," 29 Aug. 2019 Nevertheless, its success served as a proof of concept for gene drives in mammals. Quanta Magazine, "Gene Drives Work in Mice (if They’re Female)," 27 Aug. 2019 Mr Orban can point to the cluster of iron shoes near the Hungarian parliament, marking the shooting of Jews there by fascists in 1944 and 1945, as proof that his country takes history seriously. The Economist, "Historical memorials are not enough to stop anti-Semitism in Europe," 22 Aug. 2019 Now, what many are likely to see as Lam’s tepid response may be taken as proof that more extreme protest tactics are still needed. Mary Hui, Quartz, "Hong Kong’s moment of calm is in danger of being squandered," 20 Aug. 2019 Rather, they might be remembered as proof that liberty can win in the long run, when people fight for it. Jonah Goldberg, National Review, "Maybe Liberty Isn’t a Lost Cause in China," 16 Aug. 2019 This is a group that sees privilege as potential, whiteness as power, masculinity as proof of leadership prospects. Sophie Gilbert, The Atlantic, "The Patriarchal Allure of The Family," 14 Aug. 2019 As proof, Verizon points to a Federal Communications Commission preemption order from last year that attempts to limit the fees and aesthetic requirements cities and towns impose on carrier deployments. Jon Brodkin, Ars Technica, "Verizon sues city to avoid paying 5G fees, says the FCC has its back," 13 Aug. 2019 Employers are instructed not to accept them as proof of legal status, said Anastasia Tonello, a New York attorney who is the head of the American Immigration Lawyers Association. Anchorage Daily News, "How a Trump construction crew has relied on immigrants without legal status," 9 Aug. 2019

Recent Examples on the Web: Adjective

Or if your market or price club has a great deal on bulk chicken or ground beef, take advantage of it, and just divide up the package into smaller freezer-proof containers or bags. Katie Workman, Twin Cities, "8 tips for saving money on groceries," 24 July 2019 As long as the Legislature remains divided and unable to muster a veto-proof majority, that means Dunleavy’s point of view has paramount weight. James Brooks, Anchorage Daily News, "Unapologetic, Alaska Gov. Mike Dunleavy stands behind budget vetoes and $3,000 dividend," 26 July 2019 Pappas was found with a backpack and a bullet proof vest under his shirt. Chris Irvine, Fox News, "Joseph Pappas, man suspected of murdering George HW Bush's doctor, commits suicide after being confronted by police," 3 Aug. 2018 Buy Now: $14.90 for 16.7 fl oz, dermstore.com Buy Now: $6.90 for 3.3 fl oz, dermstore.com Spill-proof and TSA-proof, solid beauty products are a dopp kit no-brainer. Mara Balagtas, Condé Nast Traveler, "The Best Travel-Size Beauty Products to Pack in Your Carry-On," 10 July 2018 For anti-Trumpers, the indictments are proof positive that Donald Trump colluded with the Russians. Ian Bremmer, Time, "Yes, Obama Mishandled Russia's Election Hacking. But So Has Trump," 22 Feb. 2018 Trump’s claim that emergency powers gave him authority to impose the tariffs, as well as the severe economic costs expected to result, galvanized Senate Republicans to threaten to pass legislation blocking the tariffs with a veto-proof majority. William Hauk, The Conversation, "How Congress lost power over trade deals – and why some lawmakers want it back," 9 July 2019 Democrats already made electoral gains in 2018 that ended the GOP’s veto-proof majorities at the General Assembly. Gary D. Robertson, BostonGlobe.com, "NC redistricting fight turns to state courts after ruling," 29 June 2019 The resolution passed, 53-45, which is not a veto-proof majority. CBS News, "Senate votes to block arms sales to Saudi Arabia despite Trump veto threat," 20 June 2019

Recent Examples on the Web: Verb

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 Coyote-proofing your neighborhood To discourage coyotes from sticking around a neighborhood, Game and Fish officials have advised people to: Not feed cats and dog outdoors. Paulina Pineda, azcentral, "Dismembered cats found in Tempe neighborhood. Who — or what — is killing them?," 10 July 2019 Finally, the kouign-amanns are dusted with more sugar, brushed with more butter, and will proof for one last time before baking. Dallas News, "'Best thing I've ever eaten': Hard-to-pronounce French pastry is heavy, buttery and crisp with sugar," 20 June 2019 To critics, all this adds up to proof that Ms. Hasina seeks to dominate a nation of 165 million people. Sadanand Dhume, WSJ, "Bangladesh’s Bad Election Choice," 28 Dec. 2018

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

3 Sep 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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