from The American Heritage® Dictionary of the English Language, 4th Edition

  • abbr. Latin quod erat demonstrandum (which was to be demonstrated)

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • interj. Quod erat demonstrandum (Latin what had to be proved or what was to be demonstrated).
  • n. Quantum electrodynamics.

from the GNU version of the Collaborative International Dictionary of English

  • n. Quantum electrodynamics.


from Wiktionary, Creative Commons Attribution/Share-Alike License



  • Coulomb's law is governed by the magnitude of the vertex which is the electric charge e in QED and for the diagram above it is proportional to the square of e and is the Fine Structure Constant = 1/137.


  • Calculations starting from this picture have reproduced the experimental data by Kusch and Lamb to an astonishing degree of accuracy and modern QED is now considered to be the most exact theory in existence.

    The Nobel Prizes in Physics 1901-2000

  • This progress in QED turned out to be of the greatest importance also for the description of phenomena at higher energies.

    The Nobel Prizes in Physics 1901-2000

  • So saying that field theory is sometimes called QED, is like saying algebra is sometimes called the quadratic equation.

    Conservapedia - Recent changes [en]

  • Then the independent sales company, called QED, went to the American Film Market in Santa Monica, and they were able to raise the money from pre-selling rights to the movie, to independent distributors around the world.

    Buzzine » Peter Jackson Interview

  • It was then that Ms. Meyer and Ms. Flemal decided to start a home-schooling education service called QED (Quality Education by Design), a consulting firm that pairs parents of children in pre-K through middle school with private teachers.

    Home | The New York Observer

  • Homeschooling: Not Just for Cult Members and Celebs! introduces Melissa Meyer and Teri Flemal who have founded a company called QED (Quality Education by Design).

    HS Blog - Homeschool Blog

  • BTW, a policy on which I expressed no opinion in earlier comments (having none since it appears to involve technical legal issues of which I am totally ignorant) contrary to BdP's accusation "you apologists for government racial discrimination" - to which my only response is "QED".


  • "QED," replied Harry Forsyth, in a tone of assent which pleased the fakir mightily.

    For Fortune and Glory A Story of the Soudan War

  • "QED" was not intelligible to him, but it sounded very well indeed, he thought.

    For Fortune and Glory A Story of the Soudan War


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  • QED is too passive.

    From now on, I will end my proofs with ita ibi*

    (*so there)

    February 8, 2013