What is "incubuses"

Incubus \In"cu*bus\, n.; pl. E. Incubuses, L. Incubi. [L., the nightmare. Cf. Incubate.]

1. A demon; a fiend; a lascivious spirit, supposed to have sexual intercourse with women by night.
   --Tylor.

   The devils who appeared in the female form were generally called succubi; those who appeared like men incubi, though this distinction was not always preserved.
   --Lecky.

2. (Med.) The nightmare. See Nightmare.

   Such as are troubled with incubus, or witch-ridden, as we call it.
   --Burton.

3. Any oppressive encumbrance or burden; anything that prevents the free use of the faculties.

   Debt and usury is the incubus which weighs most heavily on the agricultural resources of Turkey.
   --J. L. Farley.

n. (plural of incubus English)