Proof conclusion

• A relativistic quantum theory of the electromagnetic interactions of photons and electrons and muons
• Proof's ending
• Gertrude Stein's first novel, published posthumously as "Things As They Are"
• Argument's conclusion
• Letters at the end of a math proof
• Proof-ending abbr
• Abbr. in math class
• Math abbr.
• Logician's letters

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
QED \Q.E.D\, QED \QED\(k[=u]"[=e]*d[=e]"), interj. [From Latin, quod erat demonstrandum, i.e. which was demonstrated.] Which was demonstrated; -- a phrase used after the conclusion of some line of reasoning, especially in mathematical or logical proofs. ...