
1) Pantomime performance 2) Theatre in the United Kingdom
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https://www.crosswordclues.com/clue/dumbshow

Dumbshow, also dumb show or dumb-show, is a traditional term for pantomime in drama, actions presented by actors onstage without spoken dialogue. It is similar to the masque. The term is most often used in regard to medieval drama and English Renaissance theatre, though it can apply in other pertinent contexts as well, as with the dammari pantomim...
Found on
http://en.wikipedia.org/wiki/Dumbshow

A mimed episode introduced into a spoken play, i.e. acting without speech.
Found on
http://www.menrath-online.de/glossaryengl.html
No exact match found.