Simon Legree vs slave driver

Simon Legree and slave driver both are nouns.

Word	Noun	Adjective	Verb	Adverb
Simon Legree	Yes	No	No	No
slave driver	Yes	No	No	No

As nouns, Simon Legree and slave driver are synonyms defined as:

Simon Legree and slave driver: a cruel employer who demands excessive work from the employees

Simon Legree (noun)	slave driver (noun)
the cruel slave dealer in an anti-slavery novel by Harriet Beecher Stowe	a supervisor of slaves at work
a cruel employer who demands excessive work from the employees	a cruel employer who demands excessive work from the employees