A bus driver was someone who drove buses for a living.
James Blake and Elias Griffin Jr were bus drivers in 1955 Montgomery, Alabama. Blake would become infamous for his part in Rosa Parks' arrest on 1 December 1955. According to Grace O'Brien, he gave all bus drivers a bad name. (TV: Rosa)
A bus driver was working on Bus 200 during Easter 2009 when it was transported through a wormhole to San Helios. His body caught fire and he was killed after his attempt to return to Earth through the wormhole. (TV: Planet of the Dead)
One bus driver was converted into a Dalek puppet. His programming became active the moment Rory Williams stepped on his bus, and teleported him into Dalek custody. (TV: Asylum of the Daleks)
Graham O'Brien was a bus driver, but was retired before becoming a companion of the Thirteenth Doctor. (TV: The Woman Who Fell to Earth, Rosa)
Graham's friends Kevin and Gabriel were also bus drivers and after Graham asked if they had seen anything strange in Sheffield, the former helped locate a Gathering Coil, while the latter only told him that his wife was going out for karaoke. (TV: The Woman Who Fell to Earth)