preludial

noun

1. anything serving as the introduction to a principal event, action, performance, etc.; preliminary part; preface; opening
2. Music
   1. an introductory instrumental composition, such as the first movement of a suite or the overture to an opera
   2. since the 19th cent., any short, romantic composition

transitive verb, intransitive verb preluded, preluding

1. to serve as or be a prelude (to)
2. to introduce by or play (as) a prelude