One who has, or attempts to acquire, a monopoly on something.(noun)
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Use "monopolist" in a sentence
"Do you mean to say that the monopolist is actually a monopsonist in an input market and a monopolist in the output market?"
""Do you mean to say that the monopolist is actually a monopsonist in an input market and a monopolist in the output market?""
"This differs from the case where a monopolist is able to make * additional* return based not on invested capital but on his unique monopoly position."