> Your definition doesn't work.

It is a recognized idiom in many English dialects:

> If people work very hard for long hours for very little money, you can refer to it as slave labor.

* https://www.collinsdictionary.com/dictionary/english/slave-l...

> very hard work for which people are paid very little

* https://dictionary.cambridge.org/dictionary/english/slave-la...

> (informal) work that is very hard and very badly paid

* https://www.oxfordlearnersdictionaries.com/definition/americ...

See also "working in the salt mines" where people do not literally take sodium chloride out of the ground.

* https://idioms.thefreedictionary.com/back+to+the+salt+mines

McDonald's workers are certainly closer to being slaves than any professor at Stanford. That's one reason California established a minimum $20/hr for foodservice work. Even when the work is largely a matter of tending machines rather than the application of hard-won culinary skills, it's still hot, dangerous, dirty, and demanding.

Is $14/hour poor remuneration?

[dead]

> Are you really going to assert that Jane Doe making $14/hr at McDonald’s is a slave

We call that "wage slavery" for a reason

Jane Doe making $14/hr at McDonald’s is absolutely a wage slave. It is different than historical chattel slavery, but no less slavery, albeit dressed up to look less offensive on the surface.