Proof is the evidence that shows something is true or valid. When you show the logical steps that take you from your hypothesis that the world is round to the conclusion that it is, you're formulating a proof.

Photographic prints that haven't been touched up are also called proofs, and that’s also what you call the first copy of a printed text, before it's checked for errors and corrected. When you check a text for errors, you're proofing. If your poker strategy is foolproof, even somebody who knows nothing about poker — a poker fool, that is — can’t get it wrong. Proof is a word you’ll see on bottles of alcohol, too: 90-proof rum means it's 45% alcohol.

Definitions of proof
  1. noun
    any factual evidence that helps to establish the truth of something
    “if you have any proof for what you say, now is the time to produce it”
    synonyms: cogent evidence
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    check, confirmation, substantiation, verification
    additional proof that something that was believed (some fact or hypothesis or theory) is correct
    establishment, validation
    the cognitive process of establishing a valid proof
    bed check
    a check that everyone is in bed by the time they should be
    an instance of confirming something by considering information from several sources
    odd-even check, parity check, redundancy check
    a system of checking for errors in computer functioning
    a digit representing the sum of the digits in an instance of digital data; used to check whether errors have occurred in transmission or storage
    type of:
    evidence, grounds
    your basis for belief or disbelief; knowledge on which to base belief
  2. noun
    a formal series of statements showing that if one thing is true something else necessarily follows from it
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    mathematical proof
    proof of a mathematical theorem
    logical proof
    proof of a logical theorem
    demonstration, monstrance
    proof by a process of argument or a series of proposition proving an asserted conclusion
    type of:
    argument, statement
    a fact or assertion offered as evidence that something is true
  3. noun
    the act of validating; finding or testing the truth of something
    synonyms: substantiation, validation
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    authentication, certification
    validating the authenticity of something or someone
    documentation, support
    documentary validation
    monetisation, monetization
    establishing something (e.g. gold or silver) as the legal tender of a country
    the act of proving that an instrument purporting to be a will was signed and executed in accord with legal requirements
    type of:
    determination, finding
    the act of determining the properties of something, usually by research or calculation
  4. noun
    (printing) an impression made to check for errors
    synonyms: test copy, trial impression
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    galley proof
    a proof taken before the type is broken up to print pages
    foundry proof
    a proof taken from a form before duplicate plates are made
    type of:
    impression, printing
    all the copies of a work printed at one time
  5. noun
    a trial photographic print from a negative
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    type of:
    photographic print, print
    a printed picture produced from a photographic negative
  6. verb
    read for errors
    synonyms: proofread
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    type of:
    ascertain, assure, check, control, ensure, insure, see, see to it
    be careful or certain to do something; make certain of something
  7. verb
    make or take a proof of, such as a photographic negative, an etching, or typeset
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    type of:
    create, make, produce
    create or manufacture a man-made product
  8. verb
    make resistant (to harm)
    proof the materials against shrinking in the dryer”
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    make safe against bombings
    make bulletproof
    child-proof, childproof
    make safe against children
    foolproof, goof-proof, goofproof
    proof against human misuse or error
    make resistant to fire
    make resistant to bad weather
    type of:
    gain strength
  9. adjective
    (used in combination or as a suffix) able to withstand
    “temptation- proof
    imperviable, impervious
    not admitting of passage or capable of being affected
  10. noun
    a measure of alcoholic strength expressed as an integer twice the percentage of alcohol present (by volume)
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    type of:
    amount, measure, quantity
    how much there is or how many there are of something that you can quantify
  11. verb
    knead to reach proper lightness
    proof dough”
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    type of:
    knead, work
    make uniform
  12. verb
    activate by mixing with water and sometimes sugar or milk
    proof yeast”
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    type of:
    alter, change, modify
    cause to change; make different; cause a transformation
Word Family

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