qed qcd • qepiq · · · Info · Definitions · Synonyms · Characters · · qed · · Text Latin · · Script 3 · · Length 1 · · Syllables Definitions · · · (noun) a relativistic quantum theory of the electromagnetic interactions of photons and electrons and muons. Synonyms: quantum electrodynamics, QED. · · Noun Definition 1 Synonyms · · · quantum electrodynamics · · Synonym 1 Characters · · d latin small letter d U+0064 e latin small letter e U+0065 q latin small letter q U+0071