1850, "the coming on of sleep," coined (as an alternative to hypnotism) from hypno- "sleep" + -osis "condition." But the distinction was not sustained, and by 1876 hypnosis was being used of artificially induced conditions.
hypno-
hypnobate
hypnopedia
hypnophobia
hypnopompic
hypnosis
hypnotherapy
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hypnotism
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