proof

noun \ ˈprüf \

Definition of proof

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

See proof defined for English-language learners

See proof defined for kids

Examples of proof in a Sentence

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.

Recent Examples of proof from the Web

The burden of proof Jackson now bears is reflected by online oddsmaker Bovada.com’s over-under propositions for his 2017 season.

— tim sullivan, The Courier-Journal, "What if Lamar Jackson is better? | Tim Sullivan," 15 Aug. 2017
There's no proof this money is going to the right place.

— amanda block, Country Living, "Stop Dedicating Cancer Walks to Me," 14 Aug. 2017
For proof, here's a video of a Samsung Galaxy S5 dropped from a height of over 1000 feet out of the window of a plane.

— juquai mcduffie, Popular Mechanics, "Here's How It Looks If You Drop Your Phone Out of a Plane," 14 Aug. 2017
But the NFL doesn’t need to meet the same standard of proof as the courts.

— claire landsbaum, The Cut, "NFL Suspends Dallas Cowboys’ Ezekiel Elliott After Domestic-Violence Investigation," 11 Aug. 2017
In 76 percent of the payments, the department could not provide proof that a company met the program’s requirement that its product or service was mainly sold outside the area where it was located.

— cynthia sewell, idahostatesman, "Head of Idaho’s Department of Labor abruptly resigns," 8 Aug. 2017
Under the new law, the burden of proof for those claims would fall on the VA, rather than veterans.

— shane sanderson, kansascity, "Congress passes bill to give veterans exposed to mustard gas another shot at benefits," 3 Aug. 2017
The latest proof is chef and Nashville-native Julia Sullivan’s temple to all things seafood, named for her grandmother and her grandfather, Edgar, a redhead.

— bon appétit, Bon Appetit, "Henrietta Red," 1 Aug. 2017
Parents of students who are new to the district should bring transfer documentation, an original birth certificate, immunization records, residency proof and a photo identification card.

— Post-Tribune, "Community news," 27 July 2017

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.

Origin and Etymology of proof

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

NEW! Time Traveler

First Known Use: 13th century

See Words from the same year

proof Synonyms

Synonyms

attestation, confirmation, corroboration, documentation, evidence, substantiation, testament, testimonial, testimony, validation, voucher, witness

Antonyms

disproof

Related Words

(the) goods; certificate, document, exhibit; demonstration, illustration; authentication, identification, manifestation, verification

Near Antonyms

rebuttal, refutation; accusation, allegation, charge; assumption, conjecture, guess, presumption, surmise, suspicion

Other Logic Terms

a posteriori, connotation, corollary, inference, mutually exclusive, paradox, postulate, syllogism

proof

adjective

Definition of proof

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

See proof defined for English-language learners

Recent Examples of proof from the Web

Manufacturers of the cladding fought additional restrictions and testing, citing the additional cost of fire-resistant or fire-proof building materials, and government regulators ultimately didn’t act.

— chas danner, Daily Intelligencer, "As Britain Races to Prevent Another High-Rise Disaster, Lax Regulation Draws Blame," 25 June 2017
Pour into a heat-proof jar and allow to cool to room temperature, uncovered.

— leah eskin, chicagotribune.com, "Genius watermelon cubes chill drinks without diluting," 19 June 2017
There are 52 Republicans in the Senate, eight members short of a filibuster-proof majority.

— joshua stewart, sandiegouniontribune.com, "Rep. Duncan Hunter: The rest of Trump's agenda depends on Senate passing health care bill," 19 June 2017
Beyond the fundamental result, such experiments also point to the possibility of hack-proof communications.

— gabriel popkin, Science | AAAS, "China’s quantum satellite achieves ‘spooky action’ at record distance," 15 June 2017
Images posted to social media appeared to show heavily armed officers in camouflage outfits and bullet-proof vests on board the plane.

— shamim adam, Bloomberg.com, "Bomb Threat From Passenger Forces Malaysia Air to Land Plane," 31 May 2017
And Mr. Scott is, in any case, a nearly spoiler-proof filmmaker.

— a. o. scott, New York Times, "Review: ‘Alien: Covenant’ Stays on Brand With Its Terror," 17 May 2017
The soft spot, the least tyrant-proof part of the government, is the U.S. Department of Justice and the larger law enforcement and regulatory apparatus of the United States government.

— conor friedersdorf, The Atlantic, "Two Dead Canaries in the Coal Mine," 11 May 2017
At the center is a snoop-proof courtroom capable of trying six alleged co-conspirators before one judge and jury.

— miamiherald, "About the 9/11 war crimes trial," 8 May 2017

First Known Use of proof

1583

Other Alcoholic Beverage Terms

finish, gimlet, mull, sake, setup, sommelier, syllabub, vintner, wassail

proof

verb

Definition of proof

transitive verb

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

See proof defined for English-language learners

Examples of proof in a Sentence

She proofed the story carefully.

Recent Examples of proof from the Web

The critical issues involved either foods at improper temperatures (tomatoes and lettuce 55° , potato salad 50° , Italian beef 115° and beef sandwiches 105° ) or improper rodent- and insect-proofing measures on kitchen doors.

— tanner walters, SI.com, "2017 MLB Ballpark Food Safety Rankings," 9 Aug. 2017
The study concluded that elevating houses and flood proofing businesses was a more economically viable option.

— sara sneath, NOLA.com, "Levee-ing the odds: Southwest Louisianians build their own flood protection," 6 Aug. 2017
Since doing this study, he’s heard from people who have thought quite deeply about germ-proofing the birthday candle blowing process though.

— sarah zhang, The Atlantic, "Blowing Out Birthday Candles Increases Cake Bacteria by 1,400 Percent," 27 July 2017
The study is aimed at providing nonstructural flood proofing recommendations to property owners for how to defend their land against future flooding.

— kate magill, Howard County Times, "One year after deadly flood, officials hope to defend Ellicott City against destruction in the future," 26 July 2017
BROWN SUGAR KITCHEN’S CORNMEAL WAFFLES WITH APPLE CIDER SYRUP Recipe in our California Cookbook » 1 hour, 15 minutes, plus proofing time.

— jonathan gold, latimes.com, "Culinary SOS: Brown Sugar Kitchen's waffle recipe," 19 July 2017
The expense of installing surge-blockers and other EMP-proofing kit on America’s big transformers is debated.

— The Economist, "The disaster that could follow from a flash in the sky," 13 July 2017
Approximately 5,000 gallons of a rust proofing material spilled into the storm sewer on June 25, with a small amount going into Lake Erie, according to Joe Reitz, the city's public works director.

— linda gandee/special to cleveland.com, cleveland.com, "Spill at Avon Lake Ford plant spills into storm sewer and Lake Erie," 30 June 2017
Here, proof the two are very much their own people, er, dogs.

— people staff, PEOPLE.com, "Contrary to Popular Belief, Exes Katy Perry and Orlando Bloom Are Not Sharing a Dog — We Have the Photographic Proof," 23 June 2017

First Known Use of proof

circa 1699

Other Printing Terms

epigraph, errata, leader, mechanical, notch, tittle, underscore, widow

PROOF Defined for English Language Learners

proof

noun

Definition of proof for English Language Learners

: 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

Definition of proof for English Language Learners

: designed or made to prevent or protect against something harmful

PROOF Defined for Kids

proof

noun \ ˈprüf \

Definition of proof for Students

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 :¹test 2

Let's put her theory to the proof.

proof

adjective

Definition of proof for Students

: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

Law Dictionary

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

4 :probate 1a

Origin and Etymology of proof

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

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See 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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proof

Definition of proof

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proof

Definition of proof

proofer

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PROOF Defined for English Language Learners

proof

Definition of proof for English Language Learners

proof

Definition of proof for English Language Learners

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proof

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proof

Definition of proof for Students

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proof

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Origin and Etymology of proof

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