Rentier often implies earning without actively working, stressing passive income. After retiring, he became a rentier, living comfortably on investment returns.
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Property Context
Use rentier when referring to income specifically from properties, not other types of investments. Renting out several houses made her a successful rentier.
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Negative Connotation
Sometimes 'rentier' has a negative connotation, seen as unearned wealth. Protesters criticized the wealthy rentiers, who profited without contributing labor.