n. [ OF. prove, proeve, F. preuve, fr. L. proba, fr. probare to prove. See Prove. ] [ 1913 Webster ]

1. Any effort, process, or operation designed to establish or discover a fact or truth; an act of testing; a test; a trial. [ 1913 Webster ]

For whatsoever mother wit or art
Could work, he put in proof. Spenser. [ 1913 Webster ]

You shall have many proofs to show your skill. Ford. [ 1913 Webster ]

Formerly, a very rude mode of ascertaining the strength of spirits was practiced, called the proof. Ure. [ 1913 Webster ]

2. That degree of evidence which convinces the mind of any truth or fact, and produces belief; a test by facts or arguments that induce, or tend to induce, certainty of the judgment; conclusive evidence; demonstration. [ 1913 Webster ]

I'll have some proof. Shak. [ 1913 Webster ]

It is no proof of a man's understanding to be able to confirm whatever he pleases. Emerson. [ 1913 Webster ]

☞ Properly speaking, proof is the effect or result of evidence, evidence is the medium of proof. Cf. Demonstration, 1. [ 1913 Webster ]

3. The quality or state of having been proved or tried; firmness or hardness that resists impression, or does not yield to force; impenetrability of physical bodies. [ 1913 Webster ]

4. Firmness of mind; stability not to be shaken. [ 1913 Webster ]

5. (Print.) A trial impression, as from type, taken for correction or examination; -- called also proof sheet. [ 1913 Webster ]

6. (Math.) A process for testing the accuracy of an operation performed. Cf. Prove, v. t., 5. [ 1913 Webster ]

7. Armor of excellent or tried quality, and deemed impenetrable; properly, armor of proof. [ Obs. ] Shak. [ 1913 Webster ]

Artist's proof, a very early proof impression of an engraving, or the like; -- often distinguished by the artist's signature. --
Proof reader, one who reads, and marks correction in, proofs. See def. 5, above. [ 1913 Webster ]

Syn. -- Testimony; evidence; reason; argument; trial; demonstration. See Testimony. [ 1913 Webster ]

a. [ 1913 Webster ]

1. Used in proving or testing; as, a proof load, or proof charge. [ 1913 Webster ]

2. Firm or successful in resisting; as, proof against harm; waterproof; bombproof. [ 1913 Webster ]

I . . . have found thee
Proof against all temptation. Milton. [ 1913 Webster ]

This was a good, stout proof article of faith. Burke. [ 1913 Webster ]

3. Being of a certain standard as to strength; -- said of alcoholic liquors. [ 1913 Webster ]

Proof charge (Firearms), a charge of powder and ball, greater than the service charge, fired in an arm, as a gun or cannon, to test its strength. --
Proof impression. See under Impression. --
Proof load (Engin.), the greatest load than can be applied to a piece, as a beam, column, etc., without straining the piece beyond the elastic limit. --
Proof sheet. See Proof, n., 5. --
Proof spirit (Chem.), a strong distilled liquor, or mixture of alcohol and water, containing not less than a standard amount of alcohol. In the United States “proof spirit is defined by law to be that mixture of alcohol and water which contains one half of its volume of alcohol, the alcohol when at a temperature of 60° Fahrenheit being of specific gravity 0.7939 referred to water at its maximum density as unity. Proof spirit has at 60° Fahrenheit a specific gravity of 0.93353, 100 parts by volume of the same consisting of 50 parts of absolute alcohol and 53.71 parts of water, ” the apparent excess of water being due to contraction of the liquids on mixture. In England proof spirit is defined by Act 58, George III., to be such as shall at a temperature of 51° Fahrenheit weigh exactly the 12/13 part of an equal measure of distilled water. This contains 49.3 per cent by weight, or 57.09 by volume, of alcohol. Stronger spirits, as those of about 60, 70, and 80 per cent of alcohol, are sometimes called second, third, and fourth proof spirits respectively. --
Proof staff, a straight-edge used by millers to test the flatness of a stone. --
Proof stick (Sugar Manuf.), a rod in the side of a vacuum pan, for testing the consistency of the sirup. --
Proof text, a passage of Scripture used to prove a doctrine. [ 1913 Webster ]

v. t. To arm with proof armor; to arm securely; as, to proof-arm herself. [ R. ] Beau. & Fl. [ 1913 Webster ]

a. Wanting sufficient evidence to induce belief; not proved. Boyle. -- Proof"less*ly, adv. [1913 Webster]

a. Proof against proofs; obstinate in the wrong. “That might have shown to any one who was not proof-proof.” Whateley. [ 1913 Webster ]