A businessman, businesswoman or businessperson was an individual that was part of a business in a revenue-generating capacity.
During a visit to Chicago in 2006, the First Doctor lost the TARDIS in a bet with a businessman named Buchanan, who intended to auction off the time machine. After travelling across several US states, the Doctor finally won the TARDIS back in Santa Monica. (PROSE: The Mother Road)
Dr Fendelman was a wealthy businessman who discovered "Eustace", a humanoid skull that predated humanity by eight million years. He later realised that the Fendahl had used him in its efforts to return to life. He was shot through the right temple by Maximillian Stael, killing him instantly. (TV: Image of the Fendahl)
The Ninth Doctor and Rose Tyler met billionaire businessman Henry van Statten in 2012. Most of his wealth had come from acquiring alien technology on the grey market, then reverse engineering it and selling the results as new inventions of his own. He keep the artefacts in a private vault. (TV: Dalek)
The American businessman Diagoras oversaw the construction of the Empire State Building. He secretly served the Cult of Skaro, and ran the work to fit the orders of Dalek Caan, who acted as the Cult's connection to the outside world. The Cult thought Diagoras was the most Dalek-like human they had encountered, as he had rare ambition and thought like a Dalek. Dalek Sec decided to merge with him to create the first human-Dalek. (TV: Daleks in Manhattan)
Nikos was a very wealthy young businessman who was a member of Lisa Deranne's Tiger Moth crew. He was killed by the Sontaran Commander Steg when he challenged their right to board the solar-yacht. (HOMEVID: Shakedown: Return of the Sontarans)