An actor's signal refers to a cue given by an actor to indicate the next move or action in a scene during a performance. Synonyms for this term include actor's cue, actor's prompt, actor's indication, actor's mark, or actor's sign. These signals can be verbal or non-verbal and are used to ensure that the performance flows smoothly and that all actors are aware of their respective roles and lines. The prompt provided by an actor is a crucial aspect of theater and helps to bring out the best in all the actors as they work together to bring a story to life on stage.