One of my favorite phrases is “Q.E.D.” It means:
which was to be shown or demonstrated (used esp. in mathematical proofs).
1810–20; < L quod erat dēmōnstrandum
QED. Dictionary.com. Dictionary.com Unabridged. Random House, Inc. http://dictionary.reference.com/browse/QED (accessed: November 16, 2009).
