Corpsing is a British theatrical slang word for when an actor unintentionally breaks character during a scene by laughing or by causing another cast member to laugh. A BBC TV programme on 18 November 2006 stated that the term "corpsing" originated when a living actor played a corpse on stage; there was sometimes a temptation to try to make that actor laugh. It is also referred to as "breaking".
Corpsing is not exclusive to the theatre, but may also include actions designed to cause hilarity in live television or radio. One of the most famous examples of this is on the cricket programme Test Match Special in the famous "leg-over" incident and another cricket commentary in which it was noted that "...the bowler's Holding, the batsman's Willey."
The term is generally used in British entertainment. In North American TV and film, when an actor corpses it is generally categorized (along with other mistakes) as a blooper.
See also 
- arts.guardian.co.uk: "A greasepaint glossary", article on theatrical terms
- BBC Sport: Test Match Legends - Brian Johnston
- Warren, Dan (16 January 2003). "A breeze for Blowers". BBC Sport (British Broadcasting Corporation). Retrieved 24 September 2012.
- Peter Cook: A Biography, Harry Thompson, Hodder and Stoughton, 1997