Select the most appropriate one-word substitution for the given group of words.

A short poem or speech addressed to the spectators after the conclusion 

Epilogue

The most appropriate one-word substitution for "a short poem or speech addressed to the spectators after the conclusion" is epilogue.

• Monologue is a long speech by one person during a conversation that stops other people from speaking or expressing an opinion.
• Glossary is a list of words and their definitions.
• Index is a list of topics or entries in a book or other publication, usually arranged alphabetically.

The word epilogue comes from the Greek word "epilōgos," meaning "afterword." An epilogue is a short speech or poem that is spoken or sung at the end of a play, movie, or book. It is often used to wrap up the story or to provide a moral or message.