blackout

noun

1. the extinguishing of all stage lights to end a play or scene
2. a comic stage skit ending with a quick blackout
an elimination or concealing of all lights that might be visible to an enemy, as during an air raid, at night
a temporary loss of electricity in an area because of a failure in its generation or transmission
a temporary loss of consciousness or vision
a loss of memory of an event or fact
suppression or concealment, as of news by censorship
☆ the prohibition of the televising of a sports event in the locality where the event takes place, so that attendance will not be reduced

See blackout in American Heritage Dictionary 4