QED

Physics.

quantum electrodynamics.

Definition for qed (2 of 2)

Q.E.D.

which was to be shown or demonstrated (used especially in mathematical proofs).

Origin of Q.E.D.

First recorded in 1810–20, Q.E.D. is from the Latin word quod erat dēmōnstrandum

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for qed

“QED” was not intelligible to him, but it sounded very well indeed, he thought.
For Fortune and Glory|Lewis Hough

British Dictionary definitions for qed

QED

abbreviation for

quod erat demonstrandum

quantum electrodynamics

Word Origin for QED

(sense 1) Latin: which was to be shown or proved

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

Word Origin and History for qed

Q.E.D.

1760, abbreviation of Latin quod erat demonstrandum "which was to be demonstrated."