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proof

n. · adj. · v.
US //ˈpɹuf// UK //pɹˈuːf// proof
  1. 1 evidence of truth (n.)
    B1 Intermediate

    information or evidence that shows something is definitely true.

    conclusive evidence or a body of facts that establishes the validity of a statement or the truth of a fact.

    Example

    The police found a video that provided clear proof of his innocence.

    Example

    The prosecution struggled to provide definitive proof of the defendant's involvement, as most of the forensic evidence had been contaminated at the scene.
    • disproof
    • refutation
    Pitfall
    I have many proofs that he is lying.
    I have proof that he is lying.

    In the sense of general evidence, 'proof' is usually uncountable. Use 'pieces of proof' or just 'proof' instead of the plural 'proofs'.

  2. 2 mathematical logic (n.)
    B2 Upper Intermediate Academic Math

    a series of logical steps used to show that a math rule is true.

    a formal sequence of logical steps, starting from axioms, that demonstrates the truth of a mathematical or logical proposition.

    Example

    The teacher asked the students to write a proof for the geometry problem.

    Example

    The mathematician spent years developing a rigorous proof for the theorem, which had remained unverified for over a century.
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  1. 3 printing/photography (n.)
    C1 Advanced Technical

    a trial copy of a document or photo used to check for mistakes before the final version is printed.

    a preliminary version of a printed piece, such as a page or photograph, produced for review and correction before the final production run.

    Example

    The author spent the afternoon checking the page proofs for spelling errors.

    Example

    Before the magazine went to press, the editor insisted on reviewing the colour proofs to ensure the photography was reproduced accurately.
  2. 4 alcohol content (n.)
    C2 Proficiency American English Technical

    a measurement of how much alcohol is in a drink.

    a measure of the ethanol content in an alcoholic beverage, traditionally defined in the US as twice the percentage of alcohol by volume.

    Example

    This whiskey is 80 proof, which means it contains 40 percent alcohol.

    Example

    The distillery produced a high-proof spirit intended specifically for blending, rather than for direct consumption.
  3. 5 resistant to (adj.)
    B2 Upper Intermediate

    able to resist or protect against something, like water or fire.

    impervious or resistant to a specific damaging agent; often used as a suffix in compound words.

    Example

    No system is completely proof against hackers if they are determined enough.

    Example

    The bunker was designed to be proof against even the most powerful conventional explosives available at the time.

    Usage

    Usually follows the noun it modifies or functions as a suffix, as in 'waterproof' or 'bulletproof'.
  4. 6 to make resistant (v.)
    C1 Advanced Technical

    to treat something so that it is protected from things like water.

    to treat a surface or material with a substance that makes it resistant to a specific external force or element.

    Example

    You should proof your boots with a special spray before going hiking in the rain.

    Example

    The contractor recommended that we proof the exterior masonry to prevent moisture from seeping into the structural timber during the winter months.
  5. 7 baking dough (v.)
    C1 Advanced Technical Cooking

    to let bread dough rise before baking it.

    to allow yeast-leavened dough to rise, typically after shaping, to achieve the desired volume and texture before baking.

    Example

    Let the rolls proof in a warm place for about an hour until they double in size.

    Example

    If you fail to proof the dough sufficiently, the resulting loaf will be dense and lack the airy crumb characteristic of a well-made sourdough.
  6. 8 to proofread (v.)
    B2 Upper Intermediate Informal

    to read through a text to find and fix mistakes.

    to read and mark corrections in a manuscript or printed proof.

    Example

    Could you proof this email for me before I send it to the boss?

    Example

    The intern was tasked to proof the final draft of the annual report, ensuring that all financial figures aligned with the provided spreadsheets.
Origin

From Middle English proof, from Old French prove, from Late Latin proba (“a proof”), from Latin probō (“to prove”); see prove; compare also the doublet probe.

Word family
Idioms2 entries

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