sadist

[ sey-dist, sad-ist ]
/ ˈseɪ dɪst, ˈsæd ɪst /

noun

Psychiatry. a person who has the condition of sadism, in which one receives sexual gratification from causing pain and degradation to another.
a person who enjoys being cruel.

VIDEO FOR SADIST

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These commonly confused words are a little sordid ... be prepared to learn the difference between the two.

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Origin of sadist

First recorded in 1890–1920; sad(ism) + -ist