proof

Concise Oxford English Dictionary © 2008 Oxford University Press:
proof/pruːf/

▶noun

• 1 evidence establishing a fact or the truth of a statement.

  ■ Law the evidence in a trial.

  ■ the proving of the truth of a statement.

  ■ a series of stages in the resolution of a mathematical or philosophical problem.

• 2 a test or trial of something.

  ■ Scots Law a trial or a civil case before a judge without a jury.

• 3 Printing a trial impression of a page used for making corrections before final printing.

  ■ a trial photographic print.

  ■ each of a limited number of impressions from an engraved plate, especially before the ordinary issue is printed.

  ■ a specially struck specimen coin with a polished or frosted finish.

• 4 the strength of distilled alcoholic spirits, relative to proof spirit taken as a standard of 100.

▶adjective [often in combination] resistant: bulletproof. ▶verb

• 1 make waterproof.

• 2 make a proof of (a printed work, engraving, etc.).

  ■ proofread (a text).

• 3 N. Amer. activate (yeast).

  ■ knead (dough) until light and smooth.

  ■ (of dough) prove.

– origin ME preve, from OFr. proeve, from late L. proba, from L. probare ‘to test, prove’; vowel change due to the influence of prove.