aside -
a line spoken by an actor to the audience but not intended for others on the stage
Adverb
aside -
in reserve; not for immediate use; "started setting aside money to buy a car"; "put something by for her old age"; "has a nest egg tucked away for a rainy day"
aside -
placed or kept separate and distinct as for a purpose; "had a feeling of being set apart"; "quality sets it apart"; "a day set aside for relaxing"
aside -
An incidental remark made quietly so as to be heard by the person to whom it is said and not by any others in the vicinity.
Adverb
aside -
To or on one side so as to be out of the way.
Wikipedia
An aside is a dramatic device in which a character speaks to the audience. By convention the audience is to realize that the character's speech is unheard by the other characters on stage. It may be addressed to the audience expressly (in character or out) or represent an unspoken thought.