A place made for showing a made thing to those gathered to watch. The watching is part of the work.
Greek θέατρον (theatron, a place for viewing), from θεᾶσθαι (theasthai, to behold); a place made for showing a made thing has always been named for the watching that happens in it, not for what is shown.
A place made for showing a made thing to those gathered to watch. The watching is part of the work, exactly as the old Greek word for the place already implied.