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succubus vs. incubus

[suhk-yuh-buhs] / ˈsʌk yə bəs /

noun

plural

succubi
  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.

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

noun

plural

incubi, incubuses
  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.