A soap opera was a type of televised entertainment.
Marcus Brooks' career went into decline after the soap opera he was on, Executive Desires, was cancelled by the network on Reef Station One. (PROSE: Synthespians™)
The Seventh Doctor once had a nightmare "where all my old foes chased me round a soap opera." (PROSE: First Frontier)
Market Square was a four-weekly soap opera filmed at the Lakeview Studios at Television Towers in London. It was set around a market. (PROSE: The Pictures of Emptiness)
Helena did not like soap operas. (PROSE: The Last Pharaoh)
The Prosperos was a hit soap opera written by William Shakespeare in the City of the Saved. (PROSE: The Book of the War)
Behind the scenes
The Seventh Doctor's mention of his nightmare involving a soap opera in First Frontier is a reference to the charity special Dimensions in Time which featured a crossover between Doctor Who and EastEnders.