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1. The evidence or argument that compels the mind to accept an assertion as true.
a. The validation of a proposition by application of specified rules, as of induction or deduction, to assumptions, axioms, and sequentially derived conclusions.
b. A statement or argument used in such a validation.
a. Convincing or persuasive demonstration: was asked for proof of his identity; an employment history that was proof of her dependability.
b. The state of being convinced or persuaded by consideration of evidence.
4. Determination of the quality of something by testing; trial: put one's beliefs to the proof.
5. Law
a. The establishment of the truth or falsity of an allegation by evidence.
b. The evidence offered in support of or in contravention of an allegation.
6. The alcoholic strength of a liquor, expressed by a number that is twice the percentage by volume of alcohol present.
7. Printing
a. A trial sheet of printed material that is made to be checked and corrected. Also called proof sheet.
b. A trial impression of a plate, stone, or block taken at any of various stages in engraving.
a. A trial photographic print.
b. Any of a limited number of newly minted coins or medals struck as specimens and for collectors from a new die on a polished planchet.
9. Archaic Proven impenetrability: "I was clothed in Armor of proof" (John Bunyan).
1. Fully or successfully resistant; impervious. Often used in combination: waterproof watches; a fireproof cellar door.
2. Of standard alcoholic strength: proof liquor.
3. Used to proofread or correct typeset copy: a proof copy of the manuscript.
v. proofed, proof·ing, proofs
1. Printing
a. To make a trial impression of (printed or engraved matter).
b. To proofread (copy).
a. To activate (dormant dry yeast) by adding water.
b. To work (dough) into proper lightness.
3. To treat so as to make resistant: proof a fabric against shrinkage.
1. Printing To proofread.
2. To become properly light for cooking: The batter proofed overnight.

[Middle English prove, preve, from Anglo-Norman prove and from Old French prueve, both from Late Latin proba, from Latin probāre, to prove; see prove.]

proof′er n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Printing, Lithography & Bookbinding) an informal name for a proofreader
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
References in periodicals archive ?
The QD printer accommodates all QD proofer handles and printheads.
One of the main images is of Robert Ross, a fire proofer from Glasgow.
All in all, the dough has risen much more consistently since we started using our ice chest proofer and the only cost to us was the porcelain light socket.
Standard evaporator coils are generally the dirtiest component in any freezer, cooler, dryer, proofer or steamer system (meaning it accounts for the most bacterial harborage points).
The new Folding Proofer from Brod & Taylor, meanwhile, prepares a wide variety of fermented foods.
fly-by-night water proofer they just can't hold a product in their
The air in a Frigoscandia proofer is tempered and humidified before it is transferred through the product zone by the fan, which provides a uniform treatment over the entire width of the belt and throughout the stack.
Nearly any type of surface can be made graffiti-proof with the application of GPA-300 Graffiti Proofer Non-Stick coating from Seicoat Corporation.
The Phenomenal Phantom Proofer offers exact match proofing with 60-second cleanup and quick roll change.
Mr Moses, who said he was working for someone else at the time, added: 'At the end of the day I'm not a damp- proofer now and I haven't been for months and months.'