Cambridge Dictionaries online Cambridge Dictionaries online

The most popular online dictionary and thesaurus for learners of English

  

QED

 
 
/ˌkjuː.iːˈdiː/ specialized

Definition

written after an argument in mathematics to show that you have proved something that you wanted to proveCalculations and calculatingAddition, subtraction, multiplication and divisionLogic and reason
(Definition of QED from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)

Word of the Day

honest-to-goodness

real or true

Word of the Day

Blog

Read our blog about how the English language behaves.

Learn More

New Words

Find words and meanings that have just started to be used in English, and let us know what you think of them.

Learn More