chauffeur
A person whose job is to drive someone for pay.
A chauffeur is a person whose job is to drive someone else's car for them, especially a luxury vehicle. The word comes from French and originally meant “stoker,” someone who kept coal fires burning in early steam-powered cars.
Today's chauffeurs drive wealthy business people, celebrities, or government officials in limousines or luxury sedans. Unlike a taxi driver who picks up many different passengers, a chauffeur typically works for one person or family, learning their preferred routes and schedules. A chauffeur often wears a uniform, holds the door open for passengers, and handles luggage.
The word can also be used playfully. If your older sister drives you to soccer practice every day, you might joke that she's your chauffeur. Or someone might say, “I'm not your chauffeur!” when they're tired of giving rides.
Interestingly, while anyone can drive a car, being a professional chauffeur requires special skills: knowing how to drive smoothly so passengers can work or relax, understanding the quickest routes, keeping the vehicle in excellent condition, and being trustworthy with private conversations overheard during trips.