A speech by an actor at the end of a play

One word substitute is Epilogue.

Epilogue: a section or speech at the end of a book or play that serves as a comment on or a conclusion to what has happened.
Monologue: a long speech by one actor in a play or film, or as part of a theatrical or broadcast programme.
Duologue: a play or part of a play with speaking roles for only two actors.
Prologue: a separate introductory section of a literary, dramatic, or musical work.