quod erat demonstrandum

American  

[kwawd e-raht dey-mawn-strahn-doom, kwod er-uht dem-uhn-stran-duhm] / kwɔd ˈɛ rɑt ˌdeɪ mɔnˈstrɑn dʊm, kwɒd ˈɛr ət ˌdɛm ənˈstræn dəm /

Latin.

1. which was to be shown or demonstrated.

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quod erat demonstrandum British  

/ ˈkwɒd ˈɛræt ˌdɛmənˈstrændʊm /

1.  QED.  (at the conclusion of a proof, esp of a theorem in Euclidean geometry) which was to be proved

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quod erat demonstrandum Cultural  

1. A phrase used to signal that a proof has just been completed. From Latin, meaning “that which was to be demonstrated.”

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Example Sentences

See Examples For:

quod erat demonstrandum

He might usefully have concluded his column with the letters we had to put next to solved mathematical equations: QED — quod erat demonstrandum — just to prove his point.

From Washington Post ● Nov. 1, 2019

QED: quod erat demonstrandum, Latin for “which was to be demonstrated or proved.”

From "Charles and Emma: The Darwins' Leap of Faith" by Deborah Heiligman

Q.E.D., quod erat demonstrandum, which was to be demonstrated.

From The New Gresham Encyclopedia. Vol. 1 Part 1 A to Amide by Various

Therefore men were originally fish, quod erat demonstrandum.

From Voltaire's Philosophical Dictionary by Voltaire

Their death is merely the quod erat demonstrandum of a mathematical and mechanical proposition.

From Impressions of a War Correspondent by Lynch, George