If someone is a “slave driver” it means that they make other people work incredibly hard. No one likes a slave driver. They are so difficult to work for and they don’t make your life happy. Many successful business people are slave drivers, but that doesn’t mean they are nice people. It just means they know how to make their staff work super hard.
A real “slave” is someone who has been taken away from their family and forced to work for zero or very low wages. Now a “slave driver” isn’t as serious as the original meaning, it just means a boss who makes their staff work too hard for too little pay.
Example: I quit my job because my boss was too much of a slave driver.
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