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 The Florida law stops companies from requiring proof of vaccination but does not ban requiring vaccinations themselves, only saying companies must not require people to provide documentation of their vaccination. Alison Durkee, Forbes, 11 Oct. 2021 Los Angeles County is now requiring proof of COVID-19 vaccination for patrons and employees at indoor bars, wineries, breweries, distilleries, nightclubs and lounges. Luke Money, Los Angeles Times, 11 Oct. 2021 Several popular cities, including San Francisco, New York, New Orleans, and Los Angeles are requiring proof of COVID vaccination for dining indoors, drinking inside bars, and at places like movie theaters, museums, and other indoor venues. Meena Thiruvengadam, Travel + Leisure, 7 Oct. 2021 McGeachin’s most recent executive order expands on one Little signed in April that banned state officials from requiring proof of vaccination from constituents trying to access government services or buildings. Washington Post, 6 Oct. 2021 McGeachin’s most recent executive order expands on one Little signed in April that banned state officials from requiring proof of vaccination from constituents trying to access government services or buildings. Jonathan Edwards, Anchorage Daily News, 6 Oct. 2021 Wiggins faced the possibility of not being allowed into Golden State’s home building at Chase Center for games starting Oct. 13 when the San Francisco Department of Public Health begins requiring proof of vaccination for large indoor events. BostonGlobe.com, 3 Oct. 2021 Theaters are not listed among those settings, but many arts venues in the state are requiring proof of vaccination for all attendees and staff, as well as masks. Christopher Arnott, courant.com, 2 Oct. 2021 Over the summer, leaders in states including Alabama, Arizona, Arkansas, Florida, Montana, Oklahoma, Tennessee and Utah barred schools and colleges from requiring proof of Covid-19 vaccinations. Jennifer Calfas, WSJ, 1 Oct. 2021 Recent Examples on the Web: Adjective The massive bill to legalize millions of undocumented immigrants, overhaul the legal immigration system and beef up border security passed with a veto-proof majority of more than two-thirds of the Senate, an overwhelming level of consensus. Deepa Fernandes, San Francisco Chronicle, 30 Sep. 2021 More than a decade later, Plant and Krauss are still proof that sometimes the best things come from unlikely collaborators. Ew Staff, EW.com, 22 Sep. 2021 The new deal will bring major benefits for ZEEL and the company’s stock prices skyrocketing soon after the announcement were proof enough. Sweta Kaushal, Forbes, 22 Sep. 2021 Look for proof points and concrete examples of how being more inclusive will help manage cognitive load, rather than increase it. Stephen Frost, Forbes, 11 May 2021 There’s also a single barrel, barrel proof version of this whiskey available as well. Jonah Flicker, Robb Report, 2 Mar. 2021 Having a spill-proof cup or a mug with a lid helps too, as some have learned the hard way. New York Times, 31 Dec. 2020 Tanzanian television aired footage showing police officers in bullet-proof vests who appeared to be wrapping a dead body outside the embassy in white material to remove it from the scene. Reuters, CNN, 26 Aug. 2021 Removable wallpaper with a peel-and-stick application is a fool-proof way to bring a plain space to life. Shivani Vyas, Better Homes & Gardens, 23 July 2021 Recent Examples on the Web: Verb The company will restore the DB6 to like-new condition and then future-proof its powertrain. Bryan Hood, Robb Report, 7 Oct. 2021 Here’s are some methods—some of them a bit surprising—to help correction-proof your portfolio. Jessica Mathews, Fortune, 24 Sep. 2021 Discover more ways of working with data and AI to future-proof your business with gfknewron — a single access point to your brand, market, and consumer intelligence, enhanced with AI-foresight and recommendations. Hayley Selby, Forbes, 16 Sep. 2021 The main difference with digital transformation is that digital acceleration can serve short-term business needs and goals while steadily upgrading the core IT that will future-proof the company. Nacho De Marco, Forbes, 29 Sep. 2021 By making the nexus in pillar 1 general, the countries have helped future-proof the rule. Robert Goulder, Forbes, 1 Sep. 2021 The moves are designed to future-proof the miner by sharpening its focus on commodities that tap into the latest mega trends. Rochelle Toplensky, WSJ, 17 Aug. 2021 Though Rigsby’s enthusiasm for a post-coronavirus world seemed to power his pedaling, the scene around him was still eerie and vacant, proof that the pandemic endures. Washington Post, 15 July 2021 Cover the dough and set aside in a warm area to proof for 1 to 2 hours, or until doubled in volume. Time, 12 Aug. 2021

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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Time Traveler for proof

Time Traveler

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

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Dictionary Entries Near proof

prooemium

proof

proof before letter

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Statistics for proof

Last Updated

13 Oct 2021

Cite this Entry

“Proof.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/proof. Accessed 24 Oct. 2021.

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More Definitions for proof

proof

noun

English Language Learners Definition of proof

 (Entry 1 of 3)

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

proof

adjective

English Language Learners Definition of proof (Entry 2 of 3)

: designed or made to prevent or protect against something harmful

proof

verb

English Language Learners Definition of proof (Entry 3 of 3)

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

More from Merriam-Webster on 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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