One who derives pleasure through cruelty or pain to others.(noun)
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Use "sadist" in a sentence
""Seidl has been described as a sadist, but underneath all the gloom and doom and constant cruelty is obviously a disappointed idealist crying out for people to care for one another.""
""The Minister of Justice can best be described as a sadist," he said in a statement."
"So the sadist is the fate of the woman; the woman the fate of the masochist."