prologue
n.
early 14c., from Old French prologue (12c.) and directly from Latin prologus, from Greek prologos "preface to a play, speaker of a prologue," literally "a speech beforehand," from pro- "before" (see pro-) + logos "discourse, speech," from legein "to speak" (see lecture, n.).
〔李〕n. 序言 [pro- =before] ←-logue [GK] =speech表示“说话”
〔蒋〕[pro-前，log言] 前言，序言
〔李〕[pro-=before前；logue=speech言→] n. speech or words before a play or poem戏剧的开场白；序诗