Definitions:

1. A short composition that serves as an introduction to a larger piece or a standalone work that sets the tone. NOUN
   • The pianist played a beautiful prelude before the main performance.
2. Something that comes before and signals the approach of something else. NOUN
   • The skirmish was merely a prelude to the full-scale war that followed.
3. To act as a precursor or preliminary to a more important action or event. VERB
   • The speech preluded the award ceremony, setting the tone for the evening.

Synonyms:

• foreword
• introduction
• overture
• preamble
• precursor
• preliminary
• prologue