quod erat demonstrandum(redirected from ERAT)
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quod erat demonstrandum
From Latin, literally "what was to be demonstrated," formally used at the conclusion of mathematical or philosophical proofs. In everyday speech and writing, it is used to emphasize that something proves a particular point or opinion. Commonly abbreviated as "QED." If the company's profits have gone up while their operating costs have gone down, then they have the money to pay their employees a better wage—quad erat demonstrat.
See also: quod
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