1. Any action, event, movement or activity of higher importance that comes before something else
2. A short introduction, opening or preliminary to another event
Before starting to read a book, a person mostly reads the first few pages for a short description of the story or introduction to the content of the book. It’s not the whole content but may be a just a short paragraph that tells you about the book. This introduction, which comes before the actual content, may be called a prelude.
1. The prelude at the beginning made me understand the entire poem without even reading it.
2. It was not just another protest march but a prelude to a bigger revolution.