A cowboy is an agricultural occupation. Cowboys are responsible for herding cattle. They are typically well trained as horseback riders and cattle roping. The term is also used to describe people who dress in the same manner of cowboys, such as country music artists.
When the G.E.E.C. computer got its' "circuits crossed," it made the country music channel and and the Opera channel's audio switch places, and so Wendy Harris noted that a "cowboy is singing opera."