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succubus vs. incubus

succubus
[suhk-yuh-buhs] / ˈsʌk yə bəs /

noun

succubi plural

  1. a demon in female form, said to have sexual intercourse with men in their sleep.

  2. any demon or evil spirit.

  3. Archaic. a strumpet; prostitute.

incubus
[in-kyuh-buhs, ing-] / ˈɪn kyə bəs, ˈɪŋ- /

noun

incubi, plural incubuses plural

  1. an imaginary demon or evil spirit supposed to descend upon sleeping persons, especially one fabled to have sexual intercourse with women during their sleep.

  2. a nightmare.

  3. something that weighs upon or oppresses one like a nightmare.