quod erat demonstrandum

[ kwawd e-raht dey-mawn-strahn-doom; English kwod er-uht dem-uhn-stran-duhm ]

Latin.
  1. which was to be shown or demonstrated.

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How to use quod erat demonstrandum in a sentence

British Dictionary definitions for quod erat demonstrandum

quod erat demonstrandum

/ Latin (ˈkwɒd ˈɛræt ˌdɛmənˈstrændʊm) /


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

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Cultural definitions for quod erat demonstrandum

quod erat demonstrandum

[ (kwawd er-aht dem-uhn-stran-duhm) ]


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

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.