Definition of quod erat demonstrandum in English:

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quod erat demonstrandum

Pronunciation: /ˌkwäd ˌerət ˌdemənˈsträndəm/
(abbreviation QED)


Used to convey that a fact or situation demonstrates the truth of one’s theory or claim, especially to mark the conclusion of a formal proof.


Latin, literally 'which was to be demonstrated'.

For editors and proofreaders

Syllabification: quod e·rat de·mon·stran·dum

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