quod erat demonstrandum

English

Etymology

From Latin quod erat dēmonstrandum (“that which was to be proved”), calqued from Ancient Greek ὅπερ ἔδει δεῖξαι (hoper edei deixai, “precisely what was required to be proved”).

Phrase

quod erat demonstrandum (plural quae erant demonstranda)

1. (something) which was to be proved; which was to be demonstrated.

Derived terms

• QED

Translations

Latin proverb

• Arabic: المطلوب إثباته (ar) (almatloub ethbatoh)
• Czech: což mělo být dokázáno (cs)
• Dutch: hetgeen te bewijzen was (nl)
• German: was zu beweisen war (de)
• Greek: όπερ έδει δείξαι (el) (óper édei deíxai) 
• Hebrew: מה שהיה להוכיח (he) (mah shehayah lehokhiach)

• Icelandic: sem sanna átti (is) n
• Polish: co było do okazania (pl)
• Swedish: vilket skulle bevisas (sv)
• Thai: ซึ่งต้องพิสูจน์ (th)

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Latin

Pronunciation

• (Classical) IPA: /kwod ˈe.rat ˌdeː.moːnsˈtran.dum/

Etymology

From quod the nominative neuter singular of quī and erat (“was”) the third-person singular imperfect active indicative of sum (“I am”) and dēmonstrandum (“proven”) nominative neuter singular of dēmonstrandus which is the future passive participle of dēmonstrō (“I demonstrate”). Literally meaning "(that) which was to be demonstrated".

Phrase

quod erat dēmonstrandum (plural quae erant dēmonstranda)

1. which was to be proved; which was to be demonstrated.

Derived terms

• QED