名詞 prelude:

1. something that serves as a preceding event or introduces what follows
   同義詞：preliminary, overture
2. music that precedes a fugue or introduces an act in an opera

動詞 prelude:

1. serve as a prelude or opening to
2. play as a prelude

1. The telephone rings and this marks the prelude to an unforeseen series of catastrophes.
   電話鈴響了，這就揭開了未預(yù)料到的大災(zāi)難的序幕。
2. His frequent depressions were the prelude to a complete mental breakdown.
   他經(jīng)常抑郁寡歡，後來精神完全崩潰了。
3. The bankruptcy of several small firms was the prelude to general economic collapse.
   幾家小商行倒閉了，隨之而來的是經(jīng)濟(jì)大蕭條。
4. The lines form a prelude to his long narrative poem.
   這幾行詩是他那長篇敘事詩的序詩。

prel.ude

n.（名詞）
An introductory performance, event, or action preceding a more important one; a preliminary or preface.
序幕：先于較重要部分的介紹性表演，事件或行動；開端或序
Music An independent piece written for piano and usually based on a single, short thematic motif.
【音樂】 序曲：一首為鋼琴所做的獨(dú)立曲目，通常以一單獨(dú)的，較短的主旋律為基調(diào)
Music A piece or movement serving as an introduction to another section or composition, especially:
【音樂】 前奏曲：作為另一部分或樂曲前奏的一部作品或樂章，尤指：
An independent, relatively long piece that precedes a fugue.
獨(dú)奏曲段：賦格曲之前的獨(dú)立的，相對較長的樂曲
The first or opening section of a suite.
組曲先前或開頭的部分
The overture to an oratorio, opera, or act of an opera.
序曲：圣樂、歌劇或一幕歌劇的序曲
A piece played before a church service; an introductory voluntary.
樂曲：在宗教禮拜樂曲前演奏的樂曲；開頭的風(fēng)琴獨(dú)奏
A relatively short composition of the 5th and early 'th centuries written in a free style, usually for piano.
隨意形式寫成的曲子：盛行于5世紀(jì)及'世紀(jì)早期通常為鋼琴所寫的相對較短的隨意體樂曲
v.（動詞）
prel.ud.ed,prel.ud.ing,prel.udes
v.tr.（及物動詞）
To serve as a prelude to.
作為前奏：作為…的序曲
To introduce with or as if with a prelude.
開頭：用或似乎用序曲來引入
v.intr.（不及物動詞）
To serve as a prelude or an introduction.
作為序幕或開端

來源：
Medieval Latin praelôdium
中世紀(jì)拉丁語 praelôdium
from Latin praelôdere [to play beforehand]
源自 拉丁語 praelôdere [預(yù)先演奏]
prae- [pre-]
prae- [前綴，表.先于.]
lôdere [to play] from lôdus [game] * see leid-
lôdere [演奏] 源自 lôdus [節(jié)目] *參見 leid-

【引伸】
prel.ud.er
n.（名詞）
prelu.dial