1670s, "commentary between two choric songs in a Greek tragedy," also "an incidental narrative or digression within a story, poem, etc.," from French épisode or directly from Greek epeisodion "an episode," literally "an addition," noun use of neuter of epeisodios "coming in besides," from epi "in addition" (see epi-) + eisodos "a coming in, entrance" (from eis "into" + hodos "way"). Transferred sense of "outstanding incident, experience" first recorded in English 1773. Transferred by 1930s to individual broadcasts of serial radio programs.