Merriam-Webster Collegiate Dictionary - prelude

 I. noun  Etymology: Middle French, from Medieval Latin praeludium, from Latin praeludere to play beforehand, from prae- + ludere to play — more at ludicrous  Date: 1561  1. an introductory performance, action, or event preceding and preparing for the principal or a more important matter  2.  a. a musical section or movement introducing the theme or chief subject (as of a fugue or suite) or serving as an introduction to an opera or oratorio  b. an opening voluntary  c. a separate concert piece usually for piano or orchestra and based entirely on a short motif  II. verb  (~d; preluding)  Date: 1655  transitive verb  1. to serve as a ~ to  2. to play as a ~  intransitive verb to give or serve as a ~; especially to play a musical introduction  • ~r noun