- the arbitrary standard strength, as of an alcoholic liquor.
- strength with reference to this standard: “100 proof” signifies a proof spirit, usually 50% alcohol.
- a trial impression, as of composed type, taken to correct errors and make alterations.
- one of a number of early and superior impressions taken before the printing of the ordinary issue: to pull a proof.
verb (used with object)
- to test the effectiveness of (yeast), as by combining with warm water so that a bubbling action occurs.
- to cause (especially bread dough) to rise due to the addition of baker's yeast or other leavening.
Origin of proof
Synonyms for proof
- the alcoholic strength of proof spirit
- the strength of a beverage or other alcoholic liquor as measured on a scale in which the strength of proof spirit is 100 degrees
Word Origin for proof
early 13c., preove "evidence to establish the fact of (something)," from Anglo-French preove, Old French prueve "proof, test, experience" (13c., Modern French preuve), from Late Latin proba "a proof," a back-formation from Latin probare "to prove" (see prove). "The devocalization of v to f ensued upon the loss of final e; cf. the relation of v and f in believe, belief, relieve, relief, behove, behoof, etc. [OED].
Meaning "act of proving" is early 14c. Meaning "act of testing or making trial of anything" is from late 14c., from influence of prove. Meaning "standard of strength of distilled liquor" is from 1705. In photography from 1855. Typographical sense of "trial impression to test type" is from c.1600. Numismatic sense of "coin struck to test a die" is from 1762; now mostly in reference to coins struck from highly polished dies, mainly for collectors.
Adjectival sense (proof against) is recorded from 1590s, from the noun in expressions such as proof of (mid-15c.), hence extended senses involving "tested power" in compounds such as fireproof (1630s), waterproof (1725), foolproof (1902), etc. Shakespeare has shame-proof.